Methods for photovoltaic absorbers with controlled group 11 stoichiometry

ABSTRACT

This invention includes processes for making a photovoltaic absorber layer having a predetermined stoichiometry on a substrate by depositing a precursor having the predetermined stoichiometry onto the substrate and converting the deposited precursor into a photovoltaic absorber material. This invention further includes processes for making a photovoltaic absorber layer having a predetermined stoichiometry on a substrate by (a) providing a polymeric precursor having the predetermined stoichiometry; (b) providing a substrate; (c) depositing the precursor onto the substrate; and (d) heating the substrate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/231,158, filed Aug. 4, 2009, U.S. Provisional Application No.61/326,540, filed Apr. 21, 2010, and U.S. Provisional Application No.61/333,689, filed May 11, 2010, each of which is hereby incorporated byreference in its entirety.

BACKGROUND

The development of photovoltaic devices such as solar cells is importantfor providing a renewable source of energy and many other uses. Thedemand for power is ever-rising as the human population increases. Inmany geographic areas, solar cells may be the only way to meet thedemand for power. The total energy from solar light impinging on theearth for one hour is about 4×10²⁰ joules. It has been estimated thatone hour of total solar energy is as much energy as is used worldwidefor an entire year. Thus, billions of square meters of efficient solarcell devices will be needed.

Photovoltaic devices are made by a variety of processes in which layersof semiconducting material are created on a substrate. Layers ofadditional materials are used to protect the photovoltaic semiconductorlayers and to conduct electrical energy out of the device. Thus, theusefulness of an optoelectronic or solar cell product is in generallimited by the nature and quality of the photovoltaic layers.

One way to produce a solar cell product involves depositing a thin,light-absorbing, solid layer of the material copper indium galliumdiselenide, known as “CIGS,” on a substrate. A solar cell having a thinfilm CIGS layer can provide low to moderate efficiency for conversion ofsunlight to electricity.

Making a CIGS semiconductor generally requires using several sourcecompounds and/or elements which contain the atoms needed for CIGS. Thesource compounds and/or elements must be formed or deposited in a thin,uniform layer on a substrate. For example, deposition of the CIGSsources can be done as a co-deposition, or as a multistep deposition.The difficulties with these approaches include lack of uniformity,purity and homogeneity of the CIGS layers, leading ultimately to limitedlight conversion efficiency.

For example, some methods for solar cells are disclosed in U.S. Pat.Nos. 5,441,897, 5,976,614, 6,518,086, 5,436,204, 5,981,868, 7,179,677,7,259,322, U.S. Patent Publication No. 2009/0280598, and PCTInternational Application Publication Nos. WO2008057119 andWO2008063190.

Other disadvantages in the production of thin film devices are limitedability to control product properties through process parameters and lowyields for commercial processes. Absorber layers suffer from theappearance of different solid phases, as well as imperfections incrystalline particles and the quantity of voids, cracks, and otherdefects in the layers. In general, CIGS materials are complex, havingmany possible solid phases. Moreover, methods for large scalemanufacturing of CIGS and related thin film solar cells can be difficultbecause of the chemical processes involved. In general, large scaleprocesses for solar cells are unpredictable because of the difficulty incontrolling numerous chemical and physical parameters involved informing an absorber layer of suitable quality on a substrate, as well asforming the other components of an efficient solar cell assembly, bothreproducibly and in high yield.

A significant problem is the inability in general to precisely controlthe stoichiometric ratios of metal atoms and Group 13 atoms in thelayers. Because several source compounds and/or elements must be used,there are many parameters to control in making and processing uniformlayers to achieve a particular stoichiometry. Many semiconductor andoptoelectronic applications are dependent on the ratios of certain metalatoms or Group 13 atoms in the material. Without direct control overthose stoichiometric ratios, processes to make semiconductor andoptoelectronic materials can be less efficient and less successful inachieving desired compositions and properties. For example, no singlesource compound is currently known that can be used to prepare a layeror film of any arbitrary stoichiometry from which CIGS materials can bemade. Compounds or compositions that can fulfill this goal have longbeen needed.

What is needed are compounds, compositions and processes to producematerials for photovoltaic layers, especially thin film layers for solarcell devices and other products.

BRIEF SUMMARY

This invention relates to methods, compounds and compositions forpreparing semiconductor and optoelectronic materials and devicesincluding thin film and band gap materials. This invention provides arange of methods, compounds and compositions directed ultimately towardphotovoltaic applications and other semiconductor materials, as well asdevices and systems for energy conversion, including solar cells. Inparticular, this invention relates to novel methods, compounds andmaterials for preparing semiconductor materials and photovoltaicabsorber materials having a controlled or predetermined stoichiometry.

This invention provides compounds, compositions, materials and methodsfor preparing semiconductors and materials, as well as optoelectronicdevices and photovoltaic layers. Among other things, this disclosureprovides precursor molecules and compositions for making and usingsemiconductors such as for photovoltaic layers, solar cells and otheruses.

The compounds and compositions of this disclosure are stable andadvantageously allow control of the stoichiometry of the atoms in thesemiconductors, particularly metal atoms and the elements of Group 13.

In various embodiments of this invention, chemically and physicallyuniform semiconductor layers can be prepared with the polymericprecursor compounds described herein.

In further embodiments, solar cells and other products can be made inprocesses operating at relatively low temperatures with the compoundsand compositions of this disclosure.

The polymeric precursor compounds and compositions of this disclosurecan provide enhanced processability for solar cell production, and theability to be processed on a variety of substrates including polymers atrelatively low temperatures.

The advantages provided by the compounds, compositions, and materials ofthis invention in making photovoltaic layers and other semiconductorsand devices are generally obtained regardless of the morphology orarchitecture of the semiconductors or devices.

This invention includes processes for making a photovoltaic absorberlayer having a predetermined stoichiometry on a substrate, the processcomprising depositing a precursor having the predetermined stoichiometryonto the substrate and converting the deposited precursor into aphotovoltaic absorber material. The precursor may be a polymericprecursor. The predetermined stoichiometry may be the stoichiometry of amonovalent metal atom or a Group 13 atom. The predeterminedstoichiometry may be the stoichiometry of Cu, Ag, In, Ga, Al, or anycombination thereof.

In some embodiments, the precursor can have a predeterminedstoichiometry according to the empirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y-t)Ga_(y)Al_(t))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum ofy plus t is from 0 to 1, z is from 0 to 1, u is from 0.5 to 1.5, v isfrom 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of whichthere are w in number, which are independently selected from alkyl,aryl, heteroaryl, alkenyl, amido, silyl, and inorganic and organicligands. The precursor may have a predetermined stoichiometry of aphotovoltaic absorber material selected from CIS, CIGS, AIS, AIGS, CAIS,CAIGS, CIGAS, AIGAS and CAIGAS.

In some aspects, one or more precursors may be deposited in an inkcomposition. The depositing may be done by spraying, spray coating,spray deposition, spray pyrolysis, printing, screen printing, inkjetprinting, aerosol jet printing, ink printing, jet printing, stamp/padprinting, transfer printing, pad printing, flexographic printing,gravure printing, contact printing, reverse printing, thermal printing,lithography, electrophotographic printing, electrodepositing,electroplating, electroless plating, bath deposition, coating, wetcoating, dip coating spin coating, knife coating, roller coating, rodcoating, slot die coating, meyerbar coating, lip direct coating,capillary coating, liquid deposition, solution deposition,layer-by-layer deposition, spin casting, solution casting, andcombinations of any of the forgoing. The substrate may be selected fromthe group of a semiconductor, a doped semiconductor, silicon, galliumarsenide, insulators, glass, molybdenum glass, silicon dioxide, titaniumdioxide, zinc oxide, silicon nitride, a metal, a metal foil, molybdenum,aluminum, beryllium, cadmium, cerium, chromium, cobalt, copper, gallium,gold, lead, manganese, molybdenum, nickel, palladium, platinum, rhenium,rhodium, silver, stainless steel, steel, iron, strontium, tin, titanium,tungsten, zinc, zirconium, a metal alloy, a metal silicide, a metalcarbide, a polymer, a plastic, a conductive polymer, a copolymer, apolymer blend, a polyethylene terephthalate, a polycarbonate, apolyester, a polyester film, a mylar, a polyvinyl fluoride,polyvinylidene fluoride, a polyethylene, a polyetherimide, apolyethersulfone, a polyetherketone, a polyimide, a polyvinylchloride,an acrylonitrile butadiene styrene polymer, a silicone, an epoxy, paper,coated paper, and combinations of any of the forgoing.

In further aspects, this invention includes processes for making aphotovoltaic absorber layer having a predetermined stoichiometry on asubstrate by (a) providing a polymeric precursor having thepredetermined stoichiometry; (b) providing a substrate; (c) depositingthe precursor onto the substrate; and (d) heating the substrate at atemperature of from about 100° C. to about 650° C. in an inertatmosphere, thereby producing a photovoltaic absorber layer having athickness of from 0.01 to 100 micrometers. The substrate may be heatedat a temperature of from about 100° C. to about 550° C., or from about200° C. to about 400° C.

This invention further encompasses a photovoltaic absorber material madeby the processes described herein, as well as a photovoltaic device madeby such processes. In certain aspects, this invention contemplatesmethods for providing electrical power using a photovoltaic device toconvert light into electrical energy.

This brief summary, taken along with the detailed description of theinvention, as well as the figures, the appended examples and claims, asa whole, encompass the disclosure of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: FIG. 1 shows an embodiment of a polymeric precursor compound(MPP). As shown in FIG. 1, the structure of the compound can berepresented by the formula (RE)₂BABABB, wherein A is the repeat unit{M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is a chalcogen, and Ris a functional group.

FIG. 2: FIG. 2 shows an embodiment of a polymeric precursor compound(MPP). As shown in FIG. 2, the structure of the compound can berepresented by the formula (RE)₂BABABBABAB, wherein A is the repeat unit{M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is a chalcogen, and Ris a functional group.

FIG. 3: FIG. 3 shows an embodiment of a polymeric precursor compound(MPP). As shown in FIG. 3, the structure of the compound can berepresented by the formula (RE)₂BA(BA)_(n)BB, wherein A is the repeatunit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is a chalcogen,and R is a functional group.

FIG. 4: FIG. 4 shows an embodiment of a polymeric precursor compound(MPP). As shown in FIG. 4, the structure of the compound can berepresented by the formula (RE)₂BA(BA)_(n)B(BA)_(m)B, wherein A is therepeat unit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is achalcogen, and R is a functional group.

FIG. 5: FIG. 5 shows an embodiment of a polymeric precursor compound(MPP). As shown in FIG. 5, the structure of the compound can berepresented by the formula ^(cyclic)(BA)₄, wherein A is the repeat unit{M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is a chalcogen, and Ris a functional group.

FIG. 6: Schematic representation of embodiments of this invention inwhich polymeric precursors and ink compositions are deposited ontoparticular substrates by methods including spraying, coating, andprinting, and are used to make semiconductor and optoelectronicmaterials and devices, as well as energy conversion systems.

FIG. 7: Schematic representation of a solar cell embodiment of thisinvention.

FIG. 8: FIG. 8 shows results of methods for preparing polymericprecursor embodiments (MPP) of this invention having predeterminedstoichiometry which are useful for preparing CIS and CIGS materials ofthe same predetermined stoichiometry. The linear correlation observed inFIG. 8 for several different polymeric precursor compounds showed thatthe stoichiometries of the polymeric precursors were preciselycontrolled by the quantities and compositions of the monomers used tomake the polymeric precursors, and that methods of this disclosure canbe used to make precursor compounds having a range of arbitrarystoichiometries.

FIG. 9: FIG. 9 shows results of methods for preparing polymericprecursor embodiments (MPP) of this invention having predeterminedstoichiometry which are useful for preparing AIS, AIGS, CAIS, and CAIGSmaterials of the same predetermined stoichiometry. The linearcorrelation observed in FIG. 9 for several different polymeric precursorcompounds showed that the stoichiometries of the polymeric precursorswere precisely controlled by the quantities and compositions of themonomers used to make the polymeric precursors, and that methods of thisdisclosure can be used to make precursor compounds having a range ofarbitrary stoichiometries.

FIG. 10: FIG. 10 shows results of methods for controlling thestoichiometry of the composition of a bulk, crystalline CIGS material.In these results, the ratio of indium to gallium was controlled. FIG. 10shows an analysis by X-ray diffraction of the structure of thecrystalline phase of bulk CIGS materials made with various polymericprecursors. The ratio of indium to gallium in the crystals of CIGSmaterials was detected by the relative positions of the 2-theta-(112)peaks in the X-ray diffraction patterns. The CIGS materials were eachmade from a polymeric precursor having a percent indium corresponding tothe value on the x-axis, where percent indium is 100*In/(In+Ga).

FIG. 11: FIG. 11 shows results of methods for controlling thestoichiometry of the composition of a bulk, crystalline AIGS material.In these results, the ratio of indium to gallium was controlled. FIG. 11shows an analysis by X-ray diffraction of the structure of thecrystalline phase of bulk AIGS materials made with various polymericprecursors. The ratio of indium to gallium in the crystals of AIGSmaterials was detected by the relative positions of the 2-theta-(112)peaks of the X-ray diffraction patterns. The AIGS materials were eachmade from a polymeric precursor having a percent indium corresponding tothe value on the x-axis, where percent indium is 100*In/(In+Ga).

FIG. 12: FIG. 12 shows results of methods for controlling thestoichiometry of the atoms of Group 13 in CIGS thin film layers. TheCIGS thin films were made by spin coating a polymeric precursorembodiment (MPP) of this invention onto a substrate, and converting thecoated polymeric precursor to a CIGS composition. The MPP polymericprecursor had a predetermined stoichiometry of Group 13 atoms, and wasused to make a CIGS thin film having the same predeterminedstoichiometry. The x-axis of FIG. 12 refers to the fraction of the Group13 atoms in the polymeric precursor that were indium atoms, whichrepresents the predetermined or targeted indium to galliumstoichiometry. The y-axis of FIG. 12 refers to the fraction of the Group13 atoms in the CIGS thin film that were indium atoms, which representsthe measured indium to gallium stoichiometry as determined by the use ofEDX. The line of unit slope represents a match between the predeterminedor targeted indium to gallium stoichiometry and the actual stoichiometryfound in the CIGS thin film.

FIG. 13: FIG. 13 shows results of methods for controlling thestoichiometry of Group 13 atoms in thin film CIGS materials. In theseresults, the ratio of indium to gallium was controlled. FIG. 13 shows ananalysis by X-ray diffraction of the structure of the crystalline phaseof CIGS thin film materials made with various polymeric precursors. TheCIGS thin films were made by coating an ink of a polymeric precursoronto a sputtered-molybdenum layer on a glass substrate, and convertingthe coating to a thin film material in a furnace. The x-axis of FIG. 13refers to the fraction of the Group 13 atoms in the thin film that wereindium atoms, which represents the indium to gallium stoichiometrymeasured by EDX. The y-axis of FIG. 13 refers to the position of the2-theta-(112) peak in the X-ray diffraction pattern of the thin filmmaterial on the substrate after conversion. The CIGS thin films wereeach made from a polymeric precursor having a percent indiumcorresponding to the same value on the x-axis. The straight line in FIG.13 is a best fit to the data points and shows a correlation between themeasured indium to gallium stoichiometry and the position of the2-theta-(112) peak of the X-ray diffraction pattern.

FIG. 14: FIG. 14 shows results of methods for preparing polymericprecursor embodiments (MPP) of this invention having predeterminedstoichiometry which are useful for preparing CAIS and CAIGS materials ofthe same predetermined stoichiometry. The linear correlation observed inFIG. 14 for several different polymeric precursor compounds showed thatthe stoichiometries of the polymeric precursors were preciselycontrolled by the quantities and compositions of the monomers used tomake the polymeric precursors, and that methods of this disclosure canbe used to make precursor compounds having a range of arbitrarymonovalent metal atom stoichiometries.

DETAILED DESCRIPTION

This invention provides a solution to a problem in making a photovoltaicabsorber layer for an optoelectronic application such as a solar cell.The problem is the inability in general to precisely control thestoichiometric quantities and ratios of metal atoms and atoms of Group13 in a process using conventional source compounds and/or elements formaking a photovoltaic absorber layer.

This invention provides a range of precursors, where each precursor canbe used alone to readily prepare a layer from which a photovoltaic layeror material of any arbitrary, predetermined stoichiometry can be made.

A precursor of this disclosure may be used to make a photovoltaic layeror material having any arbitrary, desired stoichiometry, where thestoichiometry can be selected in advance and is therefore controlled orpredetermined. Photovoltaic materials of this disclosure include CIGS,AIGS, CAIGS, CIGAS, AIGAS and CAIGAS materials, including materials thatare enriched or deficient in the quantity of a certain atom, whereCAIGAS refers to Cu/Ag/In/Ga/Al/S/Se, and further definitions are givenbelow.

In general, the ability to select a predetermined stoichiometry inadvance means that the stoichiometry is controllable.

A process for making a photovoltaic absorber material having apredetermined stoichiometry on a substrate may in general requireproviding a precursor having the predetermined stoichiometry. Thephotovoltaic absorber material is prepared from the precursor by one ofa range of processes disclosed herein. The photovoltaic absorbermaterial can retain the precise, predetermined stoichiometry of theprecursor. The processes disclosed herein therefore allow a photovoltaicabsorber material or layer having a target, predetermined stoichiometryto be made using a precursor of this invention.

In general, the precursor having the predetermined stoichiometry formaking a photovoltaic absorber material can be any precursor.

This disclosure provides a range of precursors having predeterminedstoichiometry for making semiconductor and optoelectronic materials anddevices including thin film photovoltaics and various semiconductor bandgap materials having a predetermined composition or stoichiometry.

This disclosure provides a range of novel polymeric compounds,compositions, materials and methods for semiconductor and optoelectronicmaterials and devices including thin film photovoltaics and varioussemiconductor band gap materials.

Among other advantages, the polymeric compounds, compositions, materialsand methods of this invention can provide a precursor compound formaking semiconductor and optoelectronic materials, including CIS, CIGS,AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS and CAIGAS absorber layers forsolar cells and other devices. In some embodiments, the optoelectronicsource precursor compounds of this invention can be used alone, withoutother compounds, to prepare a layer from which CIS, CIGS, AIS, AIGS,CAIS, CAIGS, CIGAS, AIGAS and CAIGAS and other materials can be made.Polymeric precursor compounds may also be used in a mixture withadditional compounds to control stoichiometry of a layer or material.

This invention provides polymeric compounds and compositions forphotovoltaic applications, as well as devices and systems for energyconversion, including solar cells.

The polymeric compounds and compositions of this disclosure includepolymeric precursor compounds and polymeric precursors for materials forpreparing novel semiconductor and photovoltaic materials, films, andproducts. Among other advantages, this disclosure provides stablepolymeric precursor compounds for making and using layered materials andphotovoltaics, such as for solar cells and other uses.

Polymeric precursors can advantageously form a thin, uniform film. Insome embodiments, a polymeric precursor is an oil that can be processedand deposited in a uniform layer on a substrate. This invention providespolymeric precursors that can be used neat to make a thin film, or canbe processed in an ink composition for deposition on a substrate. Thepolymeric precursors of this invention can have superior processabilityto form a thin film for making photovoltaic absorber layers and solarcells.

In general, the structure and properties of the polymeric compounds,compositions, and materials of this invention provide advantages inmaking photovoltaic layers, semiconductors, and devices regardless ofthe morphology, architecture, or manner of fabrication of thesemiconductors or devices.

The polymeric precursor compounds of this invention are desirable forpreparing semiconductor materials and compositions. A polymericprecursor may have a chain structure containing two or more differentmetal atoms which may be bound to each other through interactions orbridges with one or more chalcogen atoms of chalcogen-containingmoieties.

With this structure, when a polymeric precursor is used in a processsuch as deposition, coating or printing on a substrate or surface, aswell as processes involving annealing, sintering, thermal pyrolysis, andother semiconductor manufacturing processes, use of the polymericprecursors can enhance the formation of a semiconductor and itsproperties.

The polymeric precursor compounds and compositions of this invention mayadvantageously be used in processes for solar cells that avoidadditional sulfurization or selenization steps.

For example, the use of a polymeric precursor in semiconductormanufacturing processes can enhance the formation of M-E-M′ bonding,such as is required for chalcogen-containing semiconductor compounds andmaterials, wherein M is an atom of one of Groups 3 to 12, M′ is an atomof Group 13, and E is a chalcogen.

In some aspects, a polymeric precursor contains M-E-M′ bonds, and theM-E-M′ connectivity may be retained in formation of a semiconductormaterial.

A polymeric precursor compound may advantageously contain linkagesbetween atoms, where the linkages are desirably found in a material ofinterest, such as CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS andCAIGAS materials, which can be made from the polymeric precursor, or acombination of polymeric precursors.

The polymeric precursor compounds of this disclosure are stable andadvantageously allow control of the stoichiometry, structure, and ratiosof the atoms in a semiconductor material or layer, in particular, metalatoms and atoms of Group 13.

Using polymeric precursor compounds in any particular semiconductormanufacturing process, the stoichiometry of monovalent metal atoms andGroup 13 atoms can be determined and controlled. For processes operatingat relatively low temperatures, such as certain printing, spraying, anddeposition methods, the polymeric precursor compounds can maintain thedesired stoichiometry. As compared to processes involving multiplesources for semiconductor preparation, the polymeric precursors of thisinvention can provide enhanced control of the uniformity, stoichiometry,and properties of a semiconductor material.

These advantageous features allow enhanced control over the structure ofa semiconductor material made with the polymeric precursor compounds ofthis invention. The polymeric precursors of this disclosure are superiorbuilding blocks for semiconductor materials because they may provideatomic-level control of semiconductor structure.

The polymeric precursor compounds, compositions and methods of thisdisclosure may allow direct and precise control of the stoichiometricratios of metal atoms. For example, in some embodiments, a polymericprecursor can be used alone, without other compounds, to readily preparea layer from which CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS andCAIGAS materials of any arbitrary stoichiometry can be made.

In certain aspects, polymeric precursor compounds can be used to formnanoparticles that can be used in various methods to preparesemiconductor materials. Embodiments of this invention may furtherprovide processes using nanoparticles made from polymeric precursors toenhance the formation and properties of a semiconductor material.

In aspects of this invention, chemically and physically uniformsemiconductor layers can be prepared with polymeric precursor compounds.

In further embodiments, solar cells and other products canadvantageously be made in processes operating at relatively lowtemperatures using the polymeric precursor compounds and compositions ofthis disclosure.

The polymeric precursor compounds and compositions of this disclosurecan provide enhanced processability for solar cell production.

Certain polymeric precursor compounds and compositions of thisdisclosure provide the ability to be processed at relatively lowtemperatures, as well as the ability to use a variety of substratesincluding flexible polymers in solar cells.

Embodiments of Methods for Photovoltaic Absorbers with ControlledStoichiometry

Embodiments of this invention include:

A process for making a photovoltaic absorber layer having apredetermined stoichiometry on a substrate, the process comprisingdepositing a precursor having the predetermined stoichiometry onto thesubstrate and converting the deposited precursor into a photovoltaicabsorber material.

The process above wherein the precursor is a polymeric precursor. Theprocess above wherein the predetermined stoichiometry is thestoichiometry of a monovalent metal atom or a Group 13 atom. The processabove wherein the predetermined stoichiometry is the stoichiometry ofCu, Ag, In, Ga, Al, or any combination thereof.

The process above wherein the precursor has a predeterminedstoichiometry according to the empirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y-t)Ga_(y)Al_(t))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum ofy plus t is from 0 to 1, z is from 0 to 1, u is from 0.5 to 1.5, v isfrom 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of whichthere are w in number, which are independently selected from alkyl,aryl, heteroaryl, alkenyl, amido, silyl, and inorganic and organicligands. The process above wherein x is from 0 to 0.5, y is from 0 to 1,t is from 0 to 1, the sum of y plus t is from 0 to 1, z is from 0 to 1,u is from 0.7 to 1.2, v is from 0.9 to 1.1, and w is from 2 to 6. Theprocess above wherein x is from 0 to 0.3, y is from 0 to 1, t is from 0to 1, the sum of y plus t is from 0 to 1, z is from 0 to 1, u is from0.7 to 1.2, v is 1, and w is from 3 to 5. The process above wherein x isfrom 0 to 0.2, y is from 0 to 1, t is from 0 to 1, the sum of y plus tis from 0 to 1, z is from 0 to 1, u is from 0.7 to 1.2, v is 1, and w isfrom 3.5 to 4.5. The process above wherein the precursor has apredetermined stoichiometry of a photovoltaic absorber material selectedfrom CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS and CAIGAS.

The process above wherein one or more precursors are deposited in an inkcomposition. The process above wherein the depositing is done byspraying, spray coating, spray deposition, spray pyrolysis, printing,screen printing, inkjet printing, aerosol jet printing, ink printing,jet printing, stamp/pad printing, transfer printing, pad printing,flexographic printing, gravure printing, contact printing, reverseprinting, thermal printing, lithography, electrophotographic printing,electrodepositing, electroplating, electroless plating, bath deposition,coating, wet coating, dip coating spin coating, knife coating, rollercoating, rod coating, slot die coating, meyerbar coating, lip directcoating, capillary coating, liquid deposition, solution deposition,layer-by-layer deposition, spin casting, solution casting, andcombinations of any of the forgoing.

The process above wherein the substrate is selected from the group of asemiconductor, a doped semiconductor, silicon, gallium arsenide,insulators, glass, molybdenum glass, silicon dioxide, titanium dioxide,zinc oxide, silicon nitride, a metal, a metal foil, molybdenum,aluminum, beryllium, cadmium, cerium, chromium, cobalt, copper, gallium,gold, lead, manganese, molybdenum, nickel, palladium, platinum, rhenium,rhodium, silver, stainless steel, steel, iron, strontium, tin, titanium,tungsten, zinc, zirconium, a metal alloy, a metal silicide, a metalcarbide, a polymer, a plastic, a conductive polymer, a copolymer, apolymer blend, a polyethylene terephthalate, a polycarbonate, apolyester, a polyester film, a mylar, a polyvinyl fluoride,polyvinylidene fluoride, a polyethylene, a polyetherimide, apolyethersulfone, a polyetherketone, a polyimide, a polyvinylchloride,an acrylonitrile butadiene styrene polymer, a silicone, an epoxy, paper,coated paper, and combinations of any of the forgoing.

A photovoltaic absorber material made by the process above. Aphotovoltaic device made by the process above. A process for providingelectrical power comprising using a photovoltaic device to convert lightinto electrical energy.

A process for making a photovoltaic absorber layer having apredetermined stoichiometry on a substrate, the process comprising:

(a) providing a polymeric precursor having the predeterminedstoichiometry;

(b) providing a substrate;

(c) depositing the precursor onto the substrate; and

(d) heating the substrate at a temperature of from about 100° C. toabout 650° C. in an inert atmosphere, thereby producing a photovoltaicabsorber layer having a thickness of from 0.01 to 100 micrometers. Theprocess above wherein the substrate is heated at a temperature of fromabout 100° C. to about 550° C., or from about 200° C. to about 400° C.

The process above wherein the precursor has a predeterminedstoichiometry according to the empirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y-t)Ga_(y)Al_(t))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum ofy plus t is from 0 to 1, z is from 0 to 1, u is from 0.5 to 1.5, v isfrom 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of whichthere are w in number, which are independently selected from alkyl,aryl, heteroaryl, alkenyl, amido, silyl, and inorganic and organicligands. The process above wherein x is from 0 to 0.5, y is from 0 to 1,t is from 0 to 1, the sum of y plus t is from 0 to 1, z is from 0 to 1,u is from 0.7 to 1.2, v is from 0.9 to 1.1, and w is from 2 to 6. Theprocess above wherein x is from 0 to 0.3, y is from 0 to 1, t is from 0to 1, the sum of y plus t is from 0 to 1, z is from 0 to 1, u is from0.7 to 1.2, v is 1, and w is from 3 to 5. The process above wherein x isfrom 0 to 0.2, y is from 0 to 1, t is from 0 to 1, the sum of y plus tis from 0 to 1, z is from 0 to 1, u is from 0.7 to 1.2, v is 1, and w isfrom 3.5 to 4.5.

A photovoltaic absorber material made by the process above. Aphotovoltaic device made by the process above. A process for providingelectrical power comprising using a photovoltaic device to convert lightinto electrical energy.

Empirical Formulas of Precursors

This disclosure provides a range of polymeric precursor compounds havingtwo or more different metal atoms and chalcogen atoms.

In certain aspects, a polymeric precursor compound may contain metalcertain atoms and atoms of Group 13. Any of these atoms may be bonded toone or more atoms selected from atoms of Group 15, S, Se, and Te, aswell as one or more ligands.

A polymeric precursor compound may be a neutral compound, or an ionicform, or have a charged complex or counterion. In some embodiments, anionic form of a polymeric precursor compound may contain a divalentmetal atom, or a divalent metal atom as a counterion.

A polymeric precursor compound may contain atoms selected from thetransition metals of Group 3 through Group 12, B, Al, Ga, In, Tl, Si,Ge, Sn, Pb, As, Sb, and Bi. Any of these atoms may be bonded to one ormore atoms selected from atoms of Group 15, S, Se, and Te, as well asone or more ligands.

A polymeric precursor compound may contain atoms selected from Ni, Pd,Pt, Cu, Ag, Au, Zn, Cd, Hg, B, Al, Ga, In, Tl, Si, Ge, Sn, Pb, and Bi.Any of these atoms may be bonded to one or more atoms selected fromatoms of Group 15, S, Se, and Te, as well as one or more ligands.

In some embodiments, a polymeric precursor compound may contain atomsselected from Cu, Ag, Zn, Al, Ga, In, Tl, Si, Ge, Sn, and Pb. Any ofthese atoms may be bonded to one or more atoms selected from atoms ofGroup 15, S, Se, and Te, as well as one or more ligands.

In some embodiments, a polymeric precursor compound may contain atomsselected from Cu, Ag, Zn, Al, Ga, In, Tl, Si, Ge, Sn, and Pb. Any ofthese atoms may be bonded to one or more chalcogen atoms, as well as oneor more ligands.

In some variations, a polymeric precursor compound may contain atomsselected from Cu, Ag, In, Ga, and Al. Any of these atoms may be bondedto one or more atoms selected from S, Se, and Te, as well as one or moreligands.

Polymeric Precursor Structure and Properties (MPP)

A polymeric precursor compound of this disclosure is stable at ambienttemperatures. Polymeric precursors can be used for making layeredmaterials, optoelectronic materials, and devices. Using polymericprecursors advantageously allows control of the stoichiometry,structure, and ratios of various atoms in a material, layer, orsemiconductor.

Polymeric precursor compounds of this invention may be solids, solidswith low melting temperatures, semisolids, flowable solids, gums, orrubber-like solids, oily substances, or liquids at ambient temperatures,or temperatures moderately elevated from ambient. Embodiments of thisdisclosure that are fluids at temperatures moderately elevated fromambient can provide superior processability for production of solarcells and other products, as well as the enhanced ability to beprocessed on a variety of substrates including flexible substrates.

In general, a polymeric precursor compound can be processed through theapplication of heat, light, kinetic, mechanical or other energy to beconverted to a material, including a semiconductor material. In theseprocesses, a polymeric precursor compound undergoes a transition tobecome a material. The conversion of a polymeric precursor compound to amaterial can be done in processes known in the art, as well as the novelprocesses of this disclosure.

Embodiments of this invention may further provide processes for makingoptoelectronic materials. Following the synthesis of a polymericprecursor compound, the compound can be deposited, sprayed, or printedonto a substrate by various means. Conversion of the polymeric precursorcompound to a material can be done during or after the process ofdepositing, spraying, or printing the compound onto the substrate.

A polymeric precursor compound of this disclosure may have a transitiontemperature below about 400° C., or below about 300° C., or below about280° C., or below about 260° C., or below about 240° C., or below about220° C., or below about 200° C.

In some aspects, polymeric precursors of this disclosure includemolecules that are processable in a flowable form at temperatures belowabout 100° C. In certain aspects, a polymeric precursor can be fluid,liquid, flowable, flowable melt, or semisolid at relatively lowtemperatures and can be processed as a neat solid, semisolid, neatflowable liquid or melt, flowable solid, gum, rubber-like solid, oilysubstance, or liquid. In certain embodiments, a polymeric precursor isprocessable as a flowable liquid or melt at a temperature below about200° C., or below about 180° C., or below about 160° C., or below about140° C., or below about 120° C., or below about 100° C., or below about80° C., or below about 60° C., or below about 40° C.

A polymeric precursor compound of this invention can be crystalline oramorphous, and can be soluble in various non-aqueous solvents.

A polymeric precursor compound may contain ligands, or ligand fragments,or portions of ligands that can be removed under mild conditions, atrelatively low temperatures, and therefore provide a facile route toconvert the polymeric precursor to a material or semiconductor. Theligands, or some atoms of the ligands, may be removable in variousprocesses, including certain methods for depositing, spraying, andprinting, as well as by application of energy.

These advantageous features allow enhanced control over the structure ofa semiconductor material made with the polymeric precursor compounds ofthis invention.

Polymeric Precursors for Semiconductors and Optoelectronics (MPP)

This invention provides a range of polymeric precursor structures,compositions, and molecules having two or more different metal atoms.

In some embodiments, a polymeric precursor compound contains atoms M^(B)of Group 13 selected from Al, Ga, In, Tl and any combination thereof.

The atoms M^(B) may be any combination of atoms of Al, Ga, In, and Tl.The atoms M^(B) may be all of the same kind, or may be combinations ofany two, or three, or four of the atoms of Al, Ga, In, and Tl. The atomsM^(B) may be a combination of any two of the atoms of Al, Ga, In, andTl, for example, a combination of In and Ga, In and Tl, Ga and Tl, Inand Al, Ga and Al, and so forth. The atoms M^(B) may be a combination ofIn and Ga.

These polymeric precursor compounds further contain monovalent metalatoms M^(A) selected from the transition metals of Group 3 through Group12, as described above.

The atoms M^(A) may be any combination of atoms of Cu, Ag, and Au.

The polymeric precursors of this disclosure can be considered inorganicpolymers or coordination polymers.

The polymeric precursors of this disclosure may be represented indifferent ways, using different formulas to describe the same structure.

In some aspects, a polymeric precursor of this disclosure may be adistribution of polymer molecules or chains. The distribution mayencompass molecules or chains having a range of chain lengths ormolecular sizes. A polymeric precursor can be a mixture of polymers,polymer molecules or chains. The distribution of a polymeric precursorcan be centered or weighted about a particular molecular weight or chainmass.

Embodiments of this invention further provide polymeric precursors thatcan be described as AB alternating addition copolymers.

The AB alternating addition copolymer is in general composed of repeatunits A and B. The repeat units A and B are each derived from a monomer.The repeat units A and B may also be referred to as being monomers,although the empirical formula of monomer A is different from theempirical formula of repeat unit A.

The monomer for M^(A) can be M^(A)(ER), where M^(A) is as describedabove.

The monomer for M^(B) can be M^(B)(ER)₃, where M^(B) is Al, Ga, In, or acombination thereof.

In a polymeric precursor, monomers of A link to monomers of B to providea polymer chain, whether linear, cyclic, or branched, or of any othershape, that has repeat units A, each having the formula {M^(A)(ER)₂},and repeat units B, each having the formula {M^(B)(ER)₂}. The repeatunits A and B may appear in alternating order in the chain, for example,•••ABABABABAB•••.

In some embodiments, a polymeric precursor may have different atomsM^(B) selected from Al, Ga, In, or a combination thereof, where thedifferent atoms appear in random order in the structure.

The polymeric precursor compounds of this invention may be made with anydesired stoichiometry regarding the number of different metal atoms andGroup 13 atoms, and their respective stoichiometric level or ratio. Thestoichiometry of a polymeric precursor compound may be controlledthrough the concentrations of monomers, or repeating units in thepolymer chains of the precursors. A polymeric precursor compound may bemade with any desired stoichiometry regarding the number of differentmetal atoms and atoms of Group 13 and their respective stoichiometriclevels or ratios.

In some aspects, this disclosure provides polymeric precursors which areinorganic AB alternating addition copolymers having one of the followingFormulas 1 through 13:(RE)₂-[B(AB)]⁻  Formula 1(RE)₂-[(BA)_(n)B]⁻  Formula 2(RE)₂-BB(AB)_(n)  Formula 3(RE)₂-B(AB)_(n)B  Formula 4(RE)₂-B(AB)_(n)B(AB)_(m)  Formula 5(RE)₂-(BA)_(n)BB  Formula 6(RE)₂-B(BA)_(n)B  Formula 7(RE)₂-(BA)_(n)B(BA)_(m)B  Formula 8^(cyclic)(AB)_(n)  Formula 9^(cyclic)(BA)_(n)  Formula 10(RE)₂-(BB)(AABB)_(n)  Formula 11(RE)₂-(BB)(AABB)_(n)(AB)_(m)  Formula 12(RE)₂-(B)(AABB)_(n)(B)(AB)_(m)  Formula 13where A and B are as defined above, E is S, Se, or Te, and R is definedbelow.

Formulas 1 and 2 describe ionic forms that have a counterion orcounterions not shown. Examples of counterions include alkali metalions, Na, Li, and K.

The formulas RE-B(AB)_(n) and RE-(BA)_(n)B may describe stable moleculesunder certain conditions.

For example, an embodiment of a polymeric precursor compound of Formula4 is shown in FIG. 1. As shown in FIG. 1, the structure of the compoundcan be represented by the formula (RE)₂BABABB, wherein A is the repeatunit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is a chalcogen,and R is a functional group defined below.

In another example, an embodiment of a polymeric precursor compound ofFormula 5 is shown in FIG. 2. As shown in FIG. 2, the structure of thecompound can be represented by the formula (RE)₂BABABBABAB, wherein A isthe repeat unit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is achalcogen, and R is a functional group defined below.

In a further example, an embodiment of a polymeric precursor compound ofFormula 6 is shown in FIG. 3. As shown in FIG. 3, the structure of thecompound can be represented by the formula (RE)₂BA(BA)_(n)BB, wherein Ais the repeat unit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E isa chalcogen, and R is a functional group defined below.

In another example, an embodiment of a polymeric precursor compound ofFormula 8 is shown in FIG. 4. As shown in FIG. 4, the structure of thecompound can be represented by the formula (RE)₂BA(BA)_(n)B(BA)_(m)B,wherein A is the repeat unit {M^(A)(ER)₂}, B is the repeat unit{M^(B)(ER)₂}, E is a chalcogen, and R is a functional group definedbelow.

In a further example, an embodiment of a polymeric precursor compound ofFormula 10 is shown in FIG. 5. As shown in FIG. 5, the structure of thecompound can be represented by the formula ^(cyclic)(BA)₄, wherein A isthe repeat unit {M^(A)(ER)₂}, B is the repeat unit {M^(B)(ER)₂}, E is achalcogen, and R is a functional group defined below.

A polymeric precursor having one of Formulas 1-8 and 11-13 may be of anylength or molecular size. The values of n and m can be one (1) or more.In certain embodiments, the values of n and m are 2 or more, or 3 ormore, or 4 or more, or 5 or more, or 6 or more, or 7 or more, or 8 ormore, or 9 or more, or 10 or more. In some embodiments, n and m areindependently from 2 to about one million, or from 2 to about 100,000,or from 2 to about 10,000, or from 2 to about 5000, or from 2 to about1000, or from 2 to about 500, or from 2 to about 100, or from 2 to about50.

A cyclic polymeric precursor having one of Formulas 9 or 10 may be ofany molecular size. The value of n may be two (2) or more. In certainvariations, the values of n and m are 2 or more, or 3 or more, or 4 ormore, or 5 or more, or 6 or more, or 7 or more, or 8 or more, or 9 ormore, or 10 or more. In some embodiments, for cyclic Formulas 9 and 10,n is from 2 to about 50, or from 2 to about 20, or from 2 to about 16,or from 2 to about 14, or from 2 to about 12, or from 2 to about 10, orfrom 2 to about 8.

In another aspect, the repeat units {M^(B)(ER)₂} and {M^(A)(ER)₂} may beconsidered “handed” because the metal atom M^(A) and the Group 13 atomM^(B) appear on the left, while the chalcogen atom E appears to theright side. Thus, a linear terminated chain will in general require anadditional chalcogen group or groups on the left terminus, as inFormulas 1-8 and 11-13, to complete the structure. A cyclic chain, asdescribed by Formulas 9 and 10, does not require an additional chalcogengroup or groups for termination.

In certain aspects, structures of Formulas 1-8 and 11-13, where n and mare one (1), may be described as adducts. For example, adducts include(RE)₂-BBAB, (RE)₂-BABB, and (RE)₂-BABBAB.

In some embodiments, a polymeric precursor may include a structure thatis an AABB alternating block copolymer. For example, a polymericprecursor or portions of a precursor structure may contain one or moreconsecutive repeat units {AABB}. A polymeric precursor having an AABBalternating block copolymer may be represented by Formula 11 above.

In some aspects, this disclosure provides polymeric precursors which areinorganic AB alternating addition copolymers having the repeat units ofFormula 14

where atoms M^(B) are atoms of Group 13 selected from Al, Ga, In, andTl, and E is S, Se, or Te.

In certain aspects, this invention provides polymeric precursors havinga number n of the repeat units of Formula 14, where n may be 1 or more,or 2 or more, or 3 or more, or 4 or more, or 5 or more, or 6 or more, or7 or more, or 8 or more, or 9 or more, or 10 or more, or 11 or more, or12 or more.

The AB copolymer of Formula 14 may also be represented as (AB)_(n) or(BA)_(n), which represents a polymer of any chain length. Another way torepresent certain AB copolymers is the formula •••ABAB•••.

In further variations, this invention provides polymeric precursors thatmay be represented by Formula 15

where atoms M^(B1) and M^(B2) are the same or different atoms of Group13 selected from Al, Ga, In, Tl, or a combination thereof, E is S, Se,or Te, and p is one (1) or more.

In further aspects, this invention provides polymeric precursors whichmay be represented by Formula 16

where atoms M^(B1) and M^(B2) are the same or different atoms of Group13 selected from Al, Ga, In, Tl, or a combination thereof, atoms M^(A1)and M^(A2) are the same or different and are atoms selected from Cu, Au,Ag, and Hg, E is S, Se, or Te, and p is one (1) or more.

In another aspect, this disclosure provides inorganic AB alternatingcopolymers which may be represented by Formula 17••••••AB¹AB²AB³••••••  Formula 17where B¹, B², and B³ are repeat units containing atoms M^(B1), M^(B2),and M^(B3), respectively, which are atoms of Al, Ga, In, Tl or acombination thereof.

Certain empirical formulas for monomers and polymeric precursors of thisinvention are summarized in Table 1.

TABLE 1 Empirical formulas for monomers, repeat units and polymericprecursors Formula Representative Constitutional Chain Unit DescriptionA {M^(A)(ER)₂} From monomer M^(A)(ER), where M^(A) is Cu, Au, Ag B{M^(B)(ER)₂} From monomer M^(B)(ER)₃, where M^(B) is Al, Ga, In, Tl, ora combination thereof AB {M^(A)(ER)₂M^(B)(ER)₂} Polymer chain repeatunit ABA {M^(A)(ER)₂M^(B)(ER)₂M^(A)(ER)₂} An adduct, trimer, or oligomerB¹AB² {M^(B1)(ER)₂M^(A)(ER)₂M^(B2)(ER)₂} Polymer chain repeat unit,M^(B1) and M^(B2) may be the same or different, a trimer or oligomerAB¹AB² {M^(A)(ER)₂M^(B1)(ER)₂M^(A)(ER)₂M^(B2)(ER)₂} Alternatingcopolymer (AB)_(n), a tetramer or oligomer AB¹AB²AB³{M^(A)(ER)₂M^(B1)(ER)₂M^(A)(ER)₂M^(B2)(ER)₂M^(A)(ER)₂M^(B3)(ER)₂}Polymer, or an AB trimer, or an oligomer (AB)_(n) or (BA)_(n)

Polymer of any chain length •••ABAB•••

A—B—A—B

Polymer of any length, whether linear, branched, or cyclic {AABB}

A—A—B—B

AABB alternating block copolymer ^(cyclic)(AB)₄ or ^(cyclic)(BA)₄

Cyclic polymer chain, oligomer or octamer

In Table 1, the “representative constitutional chain unit” refers to therepeating unit of the polymer chain. In general, the number andappearance of electrons, ligands, or R groups in a representativeconstitutional chain repeating unit does not necessarily reflect theoxidation state of the metal atom. For example, the chain repeating unitA, which is {M^(A)(ER)₂}, arises from the monomer M^(A)(ER), where M^(A)is a metal atom of monovalent oxidation state 1 (I or one) as describedabove, or any combination of Cu, Ag and Au. It is to be understood thatthe repeating unit exists in the polymer chain bonded to two otherrepeating units, or to a repeating unit and a chain terminating unit.Likewise, the chain repeating unit B, which is {M^(B)(ER)₂}, arises fromthe monomer M^(B)(ER)₃, where M^(B) is a Group 13 atom of trivalentoxidation state 3 (III or three) selected from Al, Ga, In, Tl, and anycombination thereof, including where any one or more of those atoms arenot present. In one aspect, monomer M^(A)(ER), and monomer M^(B)(ER)₃,combine to form an AB repeating unit, which is {M^(A)(ER)₂M^(B)(ER)₂}.

In some aspects, this disclosure provides AB alternating copolymerswhich may also be alternating with respect to M^(A) or M^(B). Apolymeric precursor that is alternating with respect to M^(A) maycontain chain regions having alternating atoms M^(A1) and M^(A2). Apolymeric precursor that is alternating with respect to M^(B) maycontain chain regions having alternating atoms M^(B1) and M^(B2).

In further aspects, this disclosure provides AB alternating blockcopolymers which may contain one or more blocks of n repeat units,represented as (AB¹)_(n) or (B¹A)_(n), where the block of repeat unitscontains only one kind of atom M^(B1) selected from Group 13. A blockmay also be a repeat unit represented as (A¹B)_(n) or (BA¹)_(n), wherethe block of repeat units contains only one kind of atom M^(A1). Apolymeric precursor of this disclosure may contain one or more blocks ofrepeat units having different Group 13 atoms in each block, or differentatoms M^(A) in each block. For example, a polymeric precursor may haveone of the following formulas:(RE)₂-BB(AB¹)_(n)(AB²)_(m)  Formula 18(RE)₂-BB(AB¹)_(n)(AB²)_(m)(AB¹)_(p)  Formula 19(RE)₂-BB(AB¹)_(n)(AB²)_(m)(AB³)_(p) or(RE)₂-BB(A¹B)_(n)(A²B)_(m)(A³B)_(p)  Formula 20(RE)₂-BB(A¹B)_(n)(A²B)_(m)  Formula 21(RE)₂-BB(A¹B)_(n)(A²B)_(m)(A¹B)_(p)  Formula 22(RE)₂-BB(A¹B)_(n)(A²B)_(m)(A³B)_(p)  Formula 23where B¹, B² and B³ represent repeat units {M^(B1)(ER)₂}, {M^(B2)(ER)₂},and {M^(B3)(ER)₂}, respectively, where M^(B1), M^(B2) and M^(B3) areatoms of Group 13, each different from the other, independently selectedfrom Al, In, Ga, Tl, or a combination thereof, and where A¹, A² and A³represent repeat units {M^(A1)(ER)₂}, {M^(A2)(ER)₂}, and {M^(A3)(ER)₂},respectively, where M^(A1), M^(A2) and M^(A3) are each different fromthe other and are identified as described above for M^(A). In Formulas18 through 23, the values of n, m, and p may be 2 or more, or 3 or more,or 4 or more, or 5 or more, or 6 or more, or 7 or more, or 8 or more, or9 or more, or 10 or more, or 11 or more, or 12 or more.

In certain embodiments, an M^(B) monomer can contain a chelating group-ERE-, for example, having the formula M^(B)(ERE).

In some embodiments, a monomer may exist in a dimeric form under ambientconditions, or a trimeric or higher form, and can be used as a reagentin such forms. It is understood that the term monomer would refer to allsuch forms, whether found under ambient conditions, or found during theprocess for synthesizing a polymeric precursor from the monomer. Theformulas M^(A)(ER) and M^(B)(ER)₃, for example, should be taken toencompass the monomer in such dimeric or higher forms, if any. A monomerin a dimeric or higher form, when used as a reagent can provide themonomer form.

The polymeric precursors of this invention obtained by reacting monomersM^(A)(ER) and M^(B)(ER)₃ can be advantageously highly soluble in organicsolvent, whereas one or more of the monomers may have been insoluble.

As used herein, the terms “polymer” and “polymeric” refer to apolymerized moiety, a polymerized monomer, a repeating chain made ofrepeating units, or a polymer chain or polymer molecule. A polymer orpolymer chain may be defined by recitation of its repeating unit orunits, and may have various shapes or connectivities such as linear,branched, cyclic, and dendrimeric. Unless otherwise specified, the termspolymer and polymeric include homopolymers, copolymers, blockcopolymers, alternating polymers, terpolymers, polymers containing anynumber of different monomers, oligomers, networks, two-dimensionalnetworks, three-dimensional networks, crosslinked polymers, short andlong chains, high and low molecular weight polymer chains,macromolecules, and other forms of repeating structures such asdendrimers. Polymers include those having linear, branched and cyclicpolymer chains, and polymers having long or short branches.

As used herein, the term “polymeric component” refers to a component ofa composition, where the component is a polymer, or may form a polymerby polymerization. The term polymeric component includes a polymerizablemonomer or polymerizable molecule. A polymeric component may have anycombination of the monomers or polymers which make up any of the examplepolymers described herein, or may be a blend of polymers.

Embodiments of this invention may further provide polymeric precursorshaving polymer chain structures with repeating units. The stoichiometryof these polymeric precursors may be precisely controlled to provideaccurate levels of any desired arbitrary ratio of particular atoms.Precursor compounds having controlled stoichiometry can be used to makebulk materials, layers, and semiconductor materials having controlledstoichiometry. In some aspects, precisely controlling the stoichiometryof a polymeric precursor may be achieved by controlling thestoichiometry of the reagents, reactants, monomers or compounds used toprepare the polymeric precursor.

For the polymeric precursors of this invention, the group R in theformulas above, or a portion thereof, may be a good leaving group inrelation to a transition of the polymeric precursor compound at elevatedtemperatures or upon application of energy.

The functional groups R in the formulas above and in Table 1 may each bethe same or different from the other and are groups attached through acarbon or non-carbon atom, including alkyl, aryl, heteroaryl, alkenyl,amido, silyl, and inorganic and organic ligands. In some embodiments,the groups R are each the same or different from the other and are alkylgroups attached through a carbon atom.

In some aspects, the monomer for M^(B) can be represented asM^(B)(ER¹)₃, and the monomer for M^(A) can be represented as M^(A)(ER²),where R¹ and R² are the same or different and are groups attachedthrough a carbon or non-carbon atom, including alkyl, aryl, heteroaryl,alkenyl, amido, silyl, and inorganic and organic ligands. In someembodiments, the groups R¹ and R² are each the same or different fromthe other and are alkyl groups attached through a carbon atom.

In certain variations, the monomer for M^(B) may be M^(B)(ER¹)(ER²)₂,where R¹ and R² are different and are groups attached through a carbonor non-carbon atom, including alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. In some embodiments, thegroups R¹ and R², of M^(B)(ER¹)(ER²)₂, are different and are alkylgroups attached through a carbon atom.

In some embodiments, polymeric precursor compounds advantageously do notcontain a phosphine ligand, or a ligand or attached compound containingphosphorus, arsenic, or antimony, or a halogen ligand.

In further embodiments, the groups R may independently be (C1-22)alkylgroups. In these embodiments, the alkyl group may be a (C1)alkyl(methyl), or a (C2)alkyl (ethyl), or a (C3)alkyl, or a (C4)alkyl, or a(C5)alkyl, or a (C6)alkyl, or a (C7)alkyl, or a (C8)alkyl, or a(C9)alkyl, or a (C10)alkyl, or a (C11)alkyl, or a (C12)alkyl, or a(C13)alkyl, or a (C14)alkyl, or a (C15)alkyl, or a (C16)alkyl, or a(C17)alkyl, or a (C18)alkyl, or a (C19)alkyl, or a (C20)alkyl, or a(C21)alkyl, or a (C22)alkyl.

In certain embodiments, the groups R may independently be (C1-12)alkylgroups. In these embodiments, the alkyl group may be a (C1)alkyl(methyl), or a (C2)alkyl (ethyl), or a (C3)alkyl, or a (C4)alkyl, or a(C5)alkyl, or a (C6)alkyl, or a (C7)alkyl, or a (C8)alkyl, or a(C9)alkyl, or a (C10)alkyl, or a (C11)alkyl, or a (C12)alkyl.

In certain embodiments, the groups R may independently be (C1-6)alkylgroups. In these embodiments, the alkyl group may be a (C1)alkyl(methyl), or a (C2)alkyl (ethyl), or a (C3)alkyl, or a (C4)alkyl, or a(C5)alkyl, or a (C6)alkyl.

A polymeric precursor compound may be crystalline, or non-crystalline.

In some embodiments, a polymeric precursor may be a compound comprisingrepeating units {M^(B)(ER)(ER)} and {M^(A)(ER)(ER)}, wherein M^(A) is amonovalent metal atom selected from Cu, Au, Ag, or a combinationthereof, M^(B) is an atom of Group 13, E is S, Se, or Te, and R isindependently selected, for each occurrence, from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands. Incertain embodiments, the atoms M^(B) in the repeating units{M^(B)(ER)(ER)} are randomly selected from atoms of Group 13. In certainvariations, M^(A) is Cu, Ag, or a mixture of Cu and Ag, and the atomsM^(B) are selected from indium and gallium. E may be only selenium in apolymeric precursor, and the groups R may be independently selected, foreach occurrence, from (C1-6)alkyl.

Embodiments of this invention may further provide polymeric precursorsthat are linear, branched, cyclic, or a mixture of any of the foregoing.Some polymeric precursors may be a flowable liquid or melt at atemperature below about 100° C.

In some aspects, a polymeric precursor may contain n repeating units{M^(B)(ER)(ER)} and n repeating units {M^(A)(ER)(ER)}, wherein n is oneor more, or n is two or more, or n is three or more, or n is four ormore, or n is eight or more. The repeating units {M^(B)(ER)(ER)} and{M^(A)(ER)(ER)} may be alternating. A polymeric precursor may bedescribed by the formula (AB)_(n), wherein A is the repeat unit{M^(A)(ER)(ER)}, B is the repeat unit {M^(B)(ER)(ER)}, n is one or more,or n is two or more, and R is independently selected, for eachoccurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, andinorganic and organic ligands. In some variations, a polymeric precursormay have any one of the formulas (RE)₂-BB(AB)_(n), (RE)₂-B(AB)_(n)B,(RE)₂-B(AB)_(n)B(AB)_(m), (RE)₂-(BA)_(n)BB, (RE)₂-B(BA)_(n)B,(RE)₂-(BA)_(n)B(BA)_(m)B, ^(cyclic)(AB)_(n), ^(cyclic)(BA)_(n),(RE)₂-(BB)(AABB)_(n), (RE)₂-(BB)(AABB)_(n)(AB)_(m),(RE)₂-(B)(AABB)_(n)(B)(AB)_(m), (RE)₂-[B(AB)_(n)]⁻, and(RE)₂-[(BA)_(n)B]⁻, wherein A is the repeat unit {M^(A)(ER)(ER)}, B isthe repeat unit {M^(B)(ER)(ER)}, n is one or more, or n is two or more,and m is one or more. In further aspects, a polymeric precursor may be ablock copolymer containing one or more blocks of repeat units, whereineach block contains only one kind of atom M^(B).

A precursor compound of this disclosure may be a combination of u*(1−x)equivalents of M^(A1)(ER), u*x equivalents of M^(A2)(ER), v*(1−y−t)equivalents of M^(B1)(ER)₃, v*y equivalents of M^(B2)(ER)₃, v*tequivalents of M^(B3)(ER)₃, wherein M^(A1) is Cu and M^(A2) is Ag,M^(B1), M^(B2) and M^(B3) are different atoms of Group 13, wherein thecompound has the empirical formula (M^(A1) _(1-x)M^(A2) _(x))_(u)(M^(B1)_(1-y-t)M^(B2) _(y)M^(B3) _(t))_(v)((S_(1-z)Se_(z))R)_(w), wherein x isfrom 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum of y plus t isfrom 0 to 1, z is from 0 to 1, u is from 0.5 to 1.5, v is from 0.5 to1.5, w is from 2 to 6, and R represents R groups, of which there are win number, independently selected from alkyl, aryl, heteroaryl, alkenyl,amido, silyl, and inorganic and organic ligands. In these embodiments, aprecursor compound can have the stoichiometry useful to prepare CAIGAS,CAIGS, CIGAS, CIGS, AIGAS and AIGS materials, including materialsdeficient or enriched in the quantity of a Group 11 atom, for examplematerials deficient or enriched in Cu.

In further embodiments, a precursor compound can contain S, Se and Te.

In some embodiments, a precursor compound can be a combination ofw*(1−z) equivalents of M^(A1)(ER¹), w*z equivalents of M^(A2)(ER²), xequivalents of M^(B1)(ER³)₃, y equivalents of M^(B2)(ER⁴)₃, tequivalents of M^(B3)(ER⁵)₃, wherein M^(A1) is Cu and M^(A2) is Ag,M^(B1), M^(B2) and M^(B3) are different atoms of Group 13, wherein thecompound has the empirical formula(Cu_(1-z)Ag_(z))_(w)In_(x)Ga_(y)Al_(t)(ER¹)_(w(1-z))(ER²)_((w*z))(ER³)_(3x)(ER⁴)_(3y)(ER⁵)_(3t),w is from 0.5 to 1.5, z is from 0 to 1, x is from 0 to 1, y is from 0 to1, t is from 0 to 1, x plus y plus t is one, and wherein R¹, R², R³, R⁴and R⁵ are the same or each different, and are independently selected,for each occurrence, from alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. In these embodiments, aprecursor compound can have the stoichiometry useful to prepare CAIGAS,CAIGS, CIGAS, CIGS, AIGAS and AIGS materials, including materialsdeficient or enriched in the quantity of a Group 11 atom.

A precursor compound of this disclosure may be a combination of xequivalents of M^(A1)(ER), v*(1−y−t) equivalents of M^(B1)(ER)₃, v*yequivalents of M^(B2)(ER)₃, v*t equivalents of M^(B3)(ER)₃, whereinM^(A1) is Cu, M^(B1), M^(B2) and M^(B3) are different atoms of Group 13,wherein the compound has the empirical formula M^(A1) _(x)(M^(B1)_(1-y-t)M^(B2) _(y)M^(B3) _(t))_(v)((S_(1-z)Se_(z))R)_(w), wherein x isfrom 0.5 to 1.5, y is from 0 to 1, t is from 0 to 1, the sum of y plus tis from 0 to 1, z is from 0 to 1, v is from 0.5 to 1.5, w is from 2 to6, and R represents R groups, of which there are w in number,independently selected from alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. In these embodiments, aprecursor compound can have the stoichiometry useful to prepare CIGASand CIGS materials, including materials deficient or enriched in thequantity of a Group 11 atom.

In some embodiments, a precursor compound can be a combination of zequivalents of M^(A1)(ER¹), x equivalents of M^(B1)(ER³)₃, y equivalentsof M^(B2)(ER⁴)₃, t equivalents of M^(B3)(ER⁵)₃, wherein M^(A1) is Cu,M^(B1), M^(B2) and M^(B3) are different atoms of Group 13, wherein thecompound has the empirical formulaCu_(z)In_(x)Ga_(y)Al_(t)(ER¹)_(w(1-z))(ER²)_((w*z))(ER³)_(3x)(ER⁴)_(3y)(ER⁵)_(3t),z is from 0.5 to 1.5, x is from 0 to 1, y is from 0 to 1, t is from 0 to1, x plus y plus t is one, and wherein R¹, R², R³, R⁴ and R⁵ are thesame or each different, and are independently selected, for eachoccurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, andinorganic and organic ligands. In these embodiments, a precursorcompound can have the stoichiometry useful to prepare CIGAS and CIGSmaterials, including materials deficient in the quantity of a Group 11atom.

A precursor compound of this disclosure may be a combination of u*(1−x)equivalents of M^(A1)(ER), u*x equivalents of M^(A2)(ER), v*(1−y)equivalents of M^(B1)(ER)₃, v*y equivalents of M^(B2)(ER)₃, whereinM^(A1) is Cu and M^(A2) is Ag, M^(B1) and M^(B2) are different atoms ofGroup 13, wherein the compound has the empirical formula (M^(A1)_(1-x)M^(A2) _(x))_(u)(M^(B1) _(1-y)M^(B2)_(y))_(v)((S_(1-z)Se_(z))R)_(w), wherein x is from 0 to 1, y is from 0to 1, z is from 0 to 1, u is from 0.5 to 1.5, v is from 0.5 to 1.5, w isfrom 2 to 6, and R represents R groups, of which there are w in number,independently selected from alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. In these embodiments, aprecursor compound can have the stoichiometry useful to prepare CAIGS,CIGS and AIGS materials, including materials deficient in the quantityof a Group 11 atom.

In some embodiments, a precursor compound can be a combination ofw*(1−z) equivalents of M^(A1)(ER¹), w*z equivalents of M^(A2)(ER²), xequivalents of M^(B1)(ER³)₃, y equivalents of M^(B2)(ER⁴)₃, whereinM^(A1) is Cu and M^(A2) is Ag, M^(B1) and M^(B2) are different atoms ofGroup 13, wherein the compound has the empirical formula(Cu_(1-z)Ag_(z))_(w)In_(x)Ga_(y)(ER¹)_(w(1-z))(ER²)_((w*z))(ER³)_(3x)(ER⁴)_(3y),w is from 0.5 to 1.5, z is from 0 to 1, x is from 0 to 1, y is from 0 to1, x plus y is one, and wherein R¹, R², R³, R⁴ are the same or eachdifferent, and are independently selected, for each occurrence, fromalkyl, aryl, heteroaryl, alkenyl, amido, silyl, and inorganic andorganic ligands. In these embodiments, a precursor compound can have thestoichiometry useful to prepare CAIGS, CIGS and AIGS materials,including materials deficient or enriched in the quantity of a Group 11atom.

A precursor compound of this disclosure may be a combination of xequivalents of M^(A1)(ER), v*(1−y) equivalents of M^(B1)(ER)₃, v*yequivalents of M^(B2)(ER)₃, wherein M^(A1) is Cu, M^(B1) and M^(B2) aredifferent atoms of Group 13, wherein the compound has the empiricalformula M^(A1) _(x)(M^(B1) _(1-y)M^(B2)_(y))_(v)((S_(1-z)Se_(z))_(R))_(w), wherein x is from 0.5 to 1.5, y isfrom 0 to 1, z is from 0 to 1, v is from 0.5 to 1.5, w is from 2 to 6,and R represents R groups, of which there are w in number, independentlyselected from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, andinorganic and organic ligands. In these embodiments, a precursorcompound can have the stoichiometry useful to prepare CIGS materials,including materials deficient or enriched in the quantity of a Group 11atom.

In some embodiments, a precursor compound can be a combination of zequivalents of M^(A1)(ER¹), x equivalents of M^(B1)(ER²)₃, y equivalentsof M^(B2)(ER³)₃, wherein M^(A1) is Cu, M^(B1) and M^(B2) are differentatoms of Group 13, wherein the compound has the empirical formulaCu_(z)In_(x)Ga_(y)(ER¹)_(z)(ER²)_(3x)(ER³)_(3y), z is from 0.5 to 1.5, xis from 0 to 1, y is from 0 to 1, x plus y is one, and wherein R¹, R²,R³ are the same or each different, and are independently selected, foreach occurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl,and inorganic and organic ligands. In these embodiments, a precursorcompound can have the stoichiometry useful to prepare CIGS materials,including materials deficient or enriched in the quantity of a Group 11atom.

This disclosure provides a range of polymeric precursor compounds madeby reacting a first monomer M^(B)(ER¹)₃ with a second monomerM^(A)(ER²), where M^(A) is a monovalent metal atom, M^(B) is an atom ofGroup 13, E is S, Se, or Te, and R¹ and R² are the same or different andare independently selected from alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. The compounds may contain nrepeating units {M^(B)(ER)(ER)} and n repeating units {M^(A)(ER)(ER)},wherein n is one or more, or n is two or more, and R is defined, foreach occurrence, the same as R¹ and R².

A polymeric precursor molecule can be represented by the formula{M^(A)(ER)(ER)M^(B)(ER)(ER)}, or {M^(A)(ER)₂M^(B)(ER)₂}, which are eachunderstood to represent an {AB} repeating unit of a polymeric precursor(AB)_(n). This shorthand representation is used in the followingparagraphs to describe further examples of polymeric precursors.Further, when more than one kind of atom M^(B) is present, the amount ofeach kind may be specified in these examples by the notation (x M^(B1),yM^(B2)). For example, the polymeric compound{Cu(Se^(n)Bu)₂(In_(0.75),Ga_(0.25))(Se^(n)Bu)₂} is composed of repeatingunits, where the repeating units appear in random order, and 75% of therepeating units contain an indium atom and 25% contain a gallium atom.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Ag(Se^(sec)Bu)₄In}, {Ag_(0.6)(Se^(sec)Bu)_(3.6)In},{Ag_(0.9)(Se^(s)Bu)_(3.9)In}, {Ag_(1.5)(Se^(s)BU)_(4.5)In},{Ag(Se^(s)Bu)₃(Se^(t)Bu)In}, {Cu_(0.5)Ag_(0.5)(Se^(s)Bu)₄In},{Ag(Se^(s)Bu)₄Ga}, {Ag_(0.8)(Se^(s)Bu)_(3.8)In_(0.2)Ga_(0.8)},{Ag(Se^(s)Bu)₄In_(0.3)Ga_(0.7}, {Ag(Se) ^(s)Bu)₄In_(0.7)Ga_(0.3)},{Ag(Se^(s)Bu)₄In_(0.5)Ga_(0.5)},{Cu_(0.7)Ag_(0.1)(Se^(s)Bu)_(3.8)Ga_(0.3)In_(0.7)},{Cu_(0.8)Ag_(0.2)(Se^(s)Bu)₄In}, {Cu_(0.2)Ag_(0.8)(Se^(s)Bu)₄In},{Cu_(0.5)Ag_(0.5)(Se^(s)Bu)₄Ga_(0.5)In_(0.5)},{Cu_(0.85)Ag_(0.1)(Se^(s)Bu)_(3.95)Ga_(0.3)In_(0.7)},{Cu_(0.5)Ag_(0.5)(Se^(s)Bu)₄Ga_(0.3)In_(0.7)},{Ag(Se^(s)Bu)₃(Se^(t)Bu)Ga_(0.3)In_(0.7)},{Cu_(0.8)Ag_(0.05)(Se^(s)Bu)_(3.85)Ga_(0.3)In_(0.7)}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu_(1.40)Ag_(0.10)(Se^(t)Bu)_(1.5)(Se^(n)Bu)(In_(0.7)Ga_(0.25)Al_(0.05))(Se^(n)Bu)₂};{Cu_(1.30)Ag_(0.10)(S^(t)Bu)_(1.4)(S^(t)Bu)(In_(0.85)Ga_(0.1)Al_(0.05))(S^(t)Bu)₂};{Cu_(1.20)Ag_(0.10)(S^(t)Bu)_(1.3)(S^(n)Bu)(In_(0.80)Ga_(0.15)Al_(0.05))(S^(n)Bu)₂};{Cu_(1.10)Ag_(0.10)(Se^(t)Bu)_(1.2)(Se^(n)Bu)(In_(0.75)Ga_(0.20)Al_(0.05))(Se^(n)Bu)₂};and{Cu_(1.05)Ag_(0.05)(S^(t)Bu)_(1.1)(Se^(t)Bu)(In_(0.7)Ga_(0.2)Al_(0.1))(Se^(t)Bu)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(S^(t)Bu)(S^(i)Pr)In(S^(i)Pr)₂}; {Cu(S^(t)Bu)₂In(S^(t)Bu)₂};{Cu(S^(t)Bu)(S^(n)Bu)In(S^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(n)Bu)In(Se^(n)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂}; {Cu(Se^(t)Bu)₂Ga(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂Ga(S^(t)Bu)₂}; {Cu(Se^(t)Bu)₂In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)In(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(s)Bu)In(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)Ga(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)Ga(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se^(t)Bu)(Se^(n)Bu)In(Se^(n)Bu)₂};{Cu(S^(t)Bu)(S^(i)Pr)In(S^(i)Pr)₂}; {Cu(S^(n)Bu)(S^(t)Bu)In(S^(t)Bu)₂};{Cu(Se^(n)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂}; {Cu(S^(n)Bu)(S^(t)Bu)Ga(S^(t)Bu)₂};{Cu(Se^(s)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)In(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(s)Bu)In(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)Ga(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)Ga(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Cu(S^(t)Bu)₂(In,Ga)(S^(t)Bu)₂};{Cu(S^(t)Bu)(S^(n)Bu)(In,Ga)(S^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)₂(In,Ga)(Se^(t)Bu)₂}; {Cu(S^(t)Bu)₂(In,Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)₂(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(s)Bu)(In,Ga)(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Cu(S^(n)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(n)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(S^(t)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(S^(n)u)(S^(t)Bu)(In,Ga)(S^(t)Bu)₂};{Cu(Se^(s)Bu)(Se^(t)Bu)(In,Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(In,Ga)(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(s)Bu)(In,Tl)(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(Ga,Tl)(Se^(i)Pr)₂; and{Cu(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{(0.85Cu)(0.85Se^(t)Bu)(Se^(n)Bu)(0.7In,0.3Ga)(Se^(n)Bu)₂};{(0.9Cu)(0.9S^(t)Bu)(S^(t)Bu)(0.85In,0.15Ga)(S^(t)Bu)₂};{(0.75Cu)(0.75S^(t)Bu)(S^(n)Bu)(0.80In,0.20Ga)(S^(n)Bu)₂};{(0.8Cu)(0.8Se^(t)Bu)(Se^(n)Bu)(0.75In,0.25Ga)(Se^(n)Bu)₂};{(0.95Cu)(0.95S^(t)Bu)(Se^(t)Bu)(0.70In,0.30Ga)(Se^(t)Bu)₂};{(0.98Cu)(0.98Se^(t)Bu)(S^(t)Bu)(0.600In,0.400Ga)(S^(t)Bu)₂};{(0.835Cu)(0.835Se^(t)Bu)₂(0.9In,0.1Ga)(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂(0.8In,0.2Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)₂(0.75In,0.25Ga)(Se^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(0.67In,0.33Ga)(Se^(i)Pr)₂};{Cu(Se^(t)Bu)(S^(s)Bu)(0.875In,0.125Ga)(S^(s)Bu)₂};{Cu(Se^(t)Bu)(Se^(i)Pr)(0.99In,0.01Ga)(Se^(i)Pr)₂}; and{Cu(S^(t)Bu)(S^(i)Pr)(0.97In,0.030Ga)(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se^(s)Bu)₂In(Se^(s)Bu)₂}; {Cu(Se^(s)Bu)₂Ga(Se^(s)Bu)₂};{Cu(S^(t)Bu)₂In(S^(t)Bu)₂}; {Cu(S^(t)Bu)₂In(S^(n)Bu)₂};{Cu(Se^(t)Bu)₂Ga(Se^(n)Bu)₂}; {Cu(Se^(t)Bu)₂Ga(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂In(S^(t)Bu)₂}; {Cu(Se^(n)Bu)(Se^(t)Bu)In(Se^(t)Bu)₂};{Cu(S^(t)Bu)₂Ga(S^(t)Bu)₂}; and {Cu(Se^(n)Bu)(Se^(t)Bu)Ga(Se^(t)Bu)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se^(t)Bu)(Se^(n)Bu)(0.5In,0.5Ga)(Se^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(n)Bu)(0.75In,0.25Ga)(Se^(n)Bu)₂};{Cu(S^(t)Bu)₂(0.75In,0.25Ga)(S^(t)Bu)₂}; and{Cu(S^(t)Bu)₂(0.9In,0.1Ga)(S^(t)Bu)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Cu(Se(n-pentyl))(Se^(n)Bu)(0.5In,0.5Ga)(Se^(n)Bu)₂};{Cu(Se(n-hexyl))(Se^(n)Bu)(0.75In,0.25Ga)(Se^(n)Bu)₂};{Cu(S(n-heptyl))(S^(t)Bu)(0.75In,0.25Ga)(S^(t)Bu)₂}; and{Cu(S(n-octyl))(S^(t)Bu)(0.9In,0.1Ga)(S^(t)Bu)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{Ag(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{Ag(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Au(Se^(t)Bu)(Se^(n)Bu)In(Se^(n)Bu)₂};{Hg(S^(t)Bu)(S^(i)Pr)In(S^(i)Pr)₂};{Ag(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Ag(S^(t)Bu)₂(In,Ga)(S^(t)Bu)₂};{Au(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{Hg(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{Ag(S^(t)Bu)(S^(i)Pr)(0.9In,0.1Ga)(S^(i)Pr)₂};{Ag(S^(t)Bu)₂(0.85In,0.15Ga)(S^(t)Bu)₂};{Cu(Se^(t)Bu)(Se^(n)Bu)(0.5In,0.5 Al)(Se^(n)Bu)₂};{Cu(Se^(t)Bu)(Se^(n)Bu)(0.75In,0.25 Al)(Se^(n)Bu)₂},{(Cu,Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(Ag,Au)(S^(t)Bu)(S^(i)Pr)(In,Ga)(S^(i)Pr)₂};{(Cu,Au)(Se^(t)Bu)(Se^(n)Bu)In(Se^(n)Bu)₂}; and{(Cu,Hg)(S^(t)Bu)(S^(i)Pr)In(S^(i)Pr)₂}.

Examples of polymeric precursor compounds of this disclosure includecompounds having any one of the repeat unit formulas:{(0.95Cu,0.05Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(0.9Cu,0.1Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(0.85Cu,0.15Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(0.8Cu,0.2Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(0.75Cu,0.25Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(0.7Cu,0.3Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(0.65Cu,0.35Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(0.6Cu,0.4Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂};{(0.55Cu,0.45Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂}; and{(0.5Cu,0.5Ag)(Se^(t)Bu)(Se^(n)Bu)(In,Ga)(Se^(n)Bu)₂}.

Preparation of Polymeric Precursors (MPP)

Embodiments of this invention provide a family of polymeric precursormolecules and compositions which can be synthesized from a compoundcontaining an atom M^(B) of Group 13 selected from Al, Ga, In, Tl, or acombination thereof, and a compound containing a monovalent atom M^(A).

Advantageously facile routes for the synthesis and isolation ofpolymeric precursor compounds of this invention have been discovered, asdescribed below.

This disclosure provides a range of polymeric precursor compositionswhich can be transformed into semiconductor materials andsemiconductors. In some aspects, the polymeric precursor compositionsare precursors for the formation of semiconductor materials andsemiconductors.

In general, the polymeric precursor compositions of this invention arenon-oxide chalcogen compositions.

In some embodiments, the polymeric precursor compositions are sources orprecursors for the formation of absorber layers for solar cells,including CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS and CAIGASabsorber layers.

A polymeric precursor compound may be made with any desiredstoichiometry regarding the number of different metal atoms and atoms ofGroup 13 and their respective stoichiometric levels or ratios.

As discussed below, a polymeric precursor compound may be made byreacting monomers to produce a polymer chain. The polymeric precursorformation reactions can include initiation, propagation, andtermination.

Methods for making a polymeric precursor may include the step ofcontacting a compound M^(B)(ER)₃ with a compound M^(A)(ER), where M^(A),M^(B), E, and R are as defined above.

As shown in Reaction Scheme 1, a method for making a polymeric precursormay include the step of contacting a compound M^(B)(ER¹)₃ with acompound M^(A)(ER²), where M^(A), M^(B), and E are as defined above andthe groups R¹ and R² of the compounds may be the same or different andare as defined above.

In Reaction Scheme 1, M^(B)(ER¹)₃ and M^(A)(ER²) are monomers that formthe first adduct 1, M^(A)(ER)₂M^(B)(ER)₂. Reaction Scheme 1 representsthe initiation of a polymerization of monomers. In one aspect, ReactionScheme 1 represents the formation of the intermediate adduct AB. Ingeneral, among other steps, the polymerization reaction may form polymerchains by adding monomers to the first adduct 1, so that the firstadduct 1 may be a transient molecule that is not observed when a longerchain is ultimately produced. When additional monomers are bound toeither end of the first adduct 1, then the first adduct 1 becomes arepeating unit AB in the polymer chain.

In general, to prepare a polymeric precursor, the compounds M^(B)(ER)₃and M^(A)(ER) can be generated by various reactions.

For example, a compound M^(A)(ER) can be prepared by reacting M^(A)Xwith M⁺(ER). M⁺(ER) can be prepared by reacting E with LiR to provideLi(ER). Li(ER) can be acidified to provide HER, which can be reactedwith Na(OR) or K(OR) to provide Na(ER) and K(ER), respectively. In thesereactions, E, R and M^(A) are as defined above.

In another example, a compound M^(A)(ER) can be prepared by reactingM^(A)X with (RE)Si(CH₃)₃. The compound (RE)Si(CH₃)₃ can be made byreacting M⁺(ER) with XSi(CH₃)₃, where M⁺ is Na, Li, or K, and X ishalogen.

In another example, a compound M^(A)(ER) can be prepared by reactingM^(A) ₂O with HER. In particular, Cu(ER) can be prepared by reactingCu₂O with HER.

For example, a compound M^(B)(ER)₃ can be prepared by reacting M^(B)X₃with M⁺(ER). M⁺(ER) can be prepared as described above.

In another example, a compound M^(B)(ER)₃ can be prepared by reactingM^(B)X₃ with (RE)Si(CH₃)₃. The compound (RE)Si(CH₃)₃ can be made asdescribed above.

In another example, a compound M^(B)(ER)₃ can be prepared by reactingM^(B)R₃ with HER.

Moreover, in the preparation of a polymeric precursor, a compoundM⁺M^(B)(ER)₄ can optionally be used in place of a portion of thecompound M^(B)(ER)₃. For example, a compound M⁺M^(B)(ER)₄ can beprepared by reacting M^(B)X₃ with 4 equivalents of M⁺(ER), where M⁺ isNa, Li, or K, and X is halogen. The compound M⁺(ER) can be prepared asdescribed above.

The propagation of the polymeric precursor can be represented in part bythe formulas in Reaction Scheme 2. The formulas in Reaction Scheme 2represent only some of the reactions and additions which may occur inpropagation of the polymeric precursor.

In Reaction Scheme 2, the addition of a monomer M^(B)(ER¹)₃ orM^(A)(ER²) to the first adduct 1, may produce additional adducts 2 and3, respectively. In one aspect, Reaction Scheme 2 represents theformation of the adduct (RE)-BAB, as well as the adduct intermediateAB-M^(A)(ER). In general, the adducts 2 and 3 may be transient moietiesthat are not observed when a longer chain is ultimately produced.

The products of the initial propagation steps may continue to addmonomers in propagation. As shown in Reaction Scheme 3, adduct 2 may adda monomer M^(B)(ER¹)₃ or M^(A)(ER²).

In one aspect, Reaction Scheme 3 represents the formation of theintermediate adduct (RE)-BAB-M^(A)(ER) 4, as well as the adduct(RE)₂-BBAB 6. In general, the molecules 4, 5 and 6 may be transientmolecules that are not observed when a longer chain is ultimatelyproduced.

Other reactions and additions which may occur include the addition ofcertain propagating chains to certain other propagating chains. Forexample, as shown in Reaction Scheme 4, adduct 1 may add to adduct 2 toform a longer chain.

(R¹E)M^(B)(ER¹)₂M^(A)(ER²)(ER¹)M^(B)(ER¹)₂M^(A)(ER²)(ER¹)M^(B)(ER¹)₂  7

In one aspect, Reaction Scheme 4 represents the formation of the adduct(RE)-BABAB 7.

Any of the moieties 4, 5, 6, and 7 may be transient, and may not beobserved when a longer chain is ultimately produced.

In some variations, a propagation step may provide a stable molecule.For example, moiety 6 may be a stable molecule.

In general, AB alternating block copolymers as described in Formulas 18through 23 may be prepared by sequential addition of the correspondingmonomers M^(B1)(ER)₃, M^(B2)(ER)₃, and M^(B3)(ER)₃, when present, aswell as M^(A1)(ER), M^(A2)(ER) and M^(A3)(ER), when present, duringpolymerization or propagation.

Certain reactions or additions of the polymeric precursor propagationmay include the formation of chain branches. As shown in Reaction Scheme5, the addition of a monomer M^(A)(ER²) to the adduct molecule 2 mayproduce a branched chain 8

The propagation of the polymeric precursor can be represented in part bythe formulas in Reaction Schemes 2, 3, 4 and 5. The formulas in ReactionSchemes 2, 3, 4 and 5 represent only some representative reactions andadditions which may occur in propagation of the polymeric precursor.

Termination of the propagating polymer chain may occur by severalmechanisms. In general, because of the valencies of the atoms M^(A) andM^(B), a completed polymer chain may terminate in a M^(B) unit, but notan M^(A) unit. In some aspects, a chain terminating unit is a •••B unit,or a (ER)₂B••• unit.

In some aspects, the propagation of the polymeric precursor chain mayterminate when either of the monomers M^(B)(ER)₃ or M^(A)(ER) becomesdepleted.

In certain aspects, as shown in Reaction Scheme 6, the propagation ofthe polymeric precursor chain may terminate when a growing chainrepresented by the formula (RE)-B••••••B reacts with another chainhaving the same terminal (RE)-B unit to form a chain having the formulaB B••••••B••••••B.

In Reaction Scheme 6, two chains have combined, where the propagation ofthe polymer chain is essentially terminated and the product chain(RE)₂B••••••BB••••••B has chain terminating units that are B units.

In further aspects, the propagation of the polymeric precursor chain mayterminate when the growing chain forms a ring. As shown in ReactionScheme 7, a propagating chain such as 5 may terminate by cyclization inwhich the polymer chain forms a ring.

A polymeric precursor compound may be a single chain, or a distributionof chains having different lengths, structures or shapes, such asbranched, networked, dendrimeric, and cyclic shapes, as well ascombinations of the forgoing. A polymeric precursor compound may be anycombination of the molecules, adducts and chains described above inReaction Schemes 1 through 7.

A polymeric precursor of this disclosure may be made by the process ofproviding a first monomer compound having the formula M^(B)(ER¹)₃,providing a second monomer compound having the formula M^(A)(ER²), andcontacting the first monomer compound with the second monomer compound.In some embodiments, the first monomer compound may be a combination ofcompounds having the formulas M^(B1)(ER¹)₃ and M^(B2)(ER³)₃, whereinM^(B1) and M^(B2) are different atoms of Group 13, and R¹, R² and R³ arethe same or different and are independently selected from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands.

In some variations, the first monomer compound may be a combination ofcompounds having the formulas M^(B1)(ER¹)₃, M^(B2)(ER³)₃, andM^(B3)(ER⁴)₃, wherein M^(B1), M^(B2) and M^(B3) are atoms of Group 13each different from the other, and R³ and R⁴ are defined the same as R¹and R².

In certain aspects, the second monomer compound may be a combination ofcompounds having the formulas M^(A1)(ER²) and M^(A2)(ER³), whereinM^(A1) and M^(A2) are different atoms selected from Cu, Au, Ag, or acombination thereof, and R³ is defined the same as R¹ and R².

In further aspects, a method for making a polymeric precursor mayinclude the synthesis of a compound containing two or more atoms ofM^(B) and contacting the compound with a compound M^(A)(ER), whereM^(A), M^(B), E and R are as defined above. For example,(ER)₂M^(B1)(ER)₂M^(B2)(ER)₂ can be reacted with M^(A)(ER²), where M^(B1)and M^(B2) are the same or different atoms of Group 13.

Methods for making a polymeric precursor include embodiments in whichthe first monomer compound and the second monomer compound may becontacted in a process of depositing, spraying, coating, or printing. Incertain embodiments, the first monomer compound and the second monomercompound may be contacted at a temperature of from about −60° C. toabout 100° C.

Controlling the Stoichiometry of Atoms of Group 13 in PolymericPrecursors

A polymeric precursor compound may be made with any desiredstoichiometry with respect to the number of different metal atoms andatoms of Group 13 and their respective stoichiometric levels or ratios.

In some embodiments, the stoichiometry of a polymeric precursor compoundmay be controlled through the numbers of equivalents of the monomers inthe formation reactions.

In some aspects, the monomers M^(B1)(ER)₃, M^(B2)(ER¹)₃, M^(B3)(ER²)₃,and M^(B4)(ER³)₃ can be used for polymerization. Examples of thesemonomers are In(ER)₃, Ga(ER¹)₃, Al(ER²)₃, where the groups R, R¹, and R²are the same or different and are groups attached through a carbon ornon-carbon atom, including alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. In some embodiments, thegroups R, R¹, and R² are each the same or different from the others andare alkyl groups attached through a carbon atom.

In further aspects, the monomers M^(B1)(ER)(ER¹)₂, M^(B2)(ER²)(ER³)₂,and M^(B3)(ER⁴)(ER⁵)₂ can be used for polymerization, where the groupsR, R¹, R², R³, R⁴, and R⁵ are each the same or different from the othersand are groups attached through a carbon or non-carbon atom, includingalkyl, aryl, heteroaryl, alkenyl, amido, silyl, and inorganic andorganic ligands. In some embodiments, the groups R, R¹, R², R³, R⁴, andR⁵ are each the same or different from the others and are alkyl groupsattached through a carbon atom.

Embodiments of this invention may further provide that the stoichiometryof a polymeric precursor compound may be controlled to any desired levelthrough the adjustment of the amounts of each of the monomers providedin the formation reactions.

As shown in Reaction Scheme 8, a polymerization to form a polymericprecursor may be initiated with a mixture of monomers M^(A)(ER³),M^(B1)(ER¹)₃ and M^(B2)(ER²)₃ having any arbitrary ratios ofstoichiometry.

In Reaction Scheme 8, a polymerization can be performed with a mixtureof monomers in any desired amounts. In certain variations, apolymerization to form a polymeric precursor may be initiated with amixture of any combination of the monomers described above, where thenumber of equivalents of each monomer is adjusted to any arbitrarylevel.

In some variations, a polymerization to form a polymeric precursor canbe done using the monomers M^(A1)(ER¹), M^(A2)(ER²), and M^(A3)(ER³),for example, which can be contacted in any desired quantity to produceany arbitrary ratio of M^(A1) to M^(A2) to M^(A3).

In some aspects, for alternating copolymers of monomers M^(A)(ER) andM^(B)(ER)₃, the ratio of M^(A) to M^(B) in the polymeric precursor canbe controlled from a ratio as low as 1:2 in the unit BAB, for example,to a ratio of 1:1 in an alternating (AB)_(n) polymeric precursor, to aratio of 1.5:1 or higher. The ratio of M^(A) to M^(B) in the polymericprecursor may be 0.5 to 1.5, or 0.5 to 1, or 1 to 1, or 1 to 0.5, or 1.5to 0.5. As discussed above, in further embodiments, a polymericprecursor compound may be made with any desired stoichiometry of thenumber of different metal atoms and atoms of Group 13 and theirrespective concentration levels or ratios.

In certain aspects, a polymerization to form a polymeric precursor canbe done to form a polymeric precursor having any ratio of M^(A) toM^(B). As shown in Reaction Scheme 9, a polymeric precursor having thecomposition {p M^(A)(ER)/m M^(B1)(ER)₃/n M^(B2)(ER)₃} may be formedusing the mixture of monomers m M^(B1)(ER)₃+n M^(B2)(ER)₃+p M^(A)(ER).

In certain variations, any number of monomers of M^(A)(ER) and anynumber of monomers of M^(B)(ER)₃ can be used in the formation reactions.For example, a polymeric precursor may be made with the monomersM^(A1)(ER), M^(A2)(ER), M^(A3)(ER), M^(B1)(ER)₃, M^(B2)(ER¹)₃,M^(B3)(ER²)₃, and M^(B4)(ER³)₃, where the number of equivalents of eachmonomer is an independent and arbitrary amount.

For example, the ratios of the atoms M^(A):M^(B) in a polymericprecursor may be about 0.5:1 or greater, or about 0.6:1 or greater, orabout 0.7:1 or greater, or about 0.8:1 or greater, or about 0.9:1 orgreater, or about 0.95:1 or greater. In certain variations, the ratiosof the atoms M^(A):M^(B) in a polymeric precursor may be about 1:1 orgreater, or about 1.1:1 or greater.

In further examples, the ratios of the atoms M^(A):M^(B) in a polymericprecursor may be from about 0.5 to about 1.2, or from about 0.6 to about1.2, or from about 0.7 to about 1.1, or from about 0.8 to about 1.1, orfrom about 0.8 to about 1, or from about 0.9 to about 1. In someexamples, the ratios of the atoms M^(A):M^(B) in a polymeric precursormay be about 0.80, or about 0.82, or about 0.84, or about 0.86, or about0.88, or about 0.90, or about 0.92, or about 0.94, or about 0.96, orabout 0.98, or about 1.00, or about 1.02, or about 1.1, or about 1.2, orabout 1.3, or about 1.5. In the foregoing ratios M^(A):M^(B), the ratiorefers to the sum of all atoms of M^(A) or M^(B), respectively, whenthere are more than one kind of M^(A) or M^(B), such as M^(A1) andM^(A2) and M^(B1) and M^(B2).

As shown in Reaction Scheme 10, a polymeric precursor compound havingthe repeating unit composition {M^(A)(ER)₂(m M^(B1),n M^(B2))(ER)₂} maybe formed using the mixture of monomers m M^(B1)(ER)₃+nM^(B2)(ER)₃+M^(A)(ER).

In Reaction Scheme 10, the sum of m and n is one.

Embodiments of this invention may further provide a polymeric precursormade from monomers of M^(A)(ER) and M^(B)(ER)₃, where the total numberof equivalents of monomers of M^(A)(ER) is less than the total number ofequivalents of monomers of M^(B)(ER)₃. In certain embodiments, apolymeric precursor may be made that is substoichiometric or deficientin atoms of M^(A) relative to atoms of M^(B).

As used herein, the expression M^(A) is deficient, or M^(A) is deficientto M^(B) refers to a composition or formula in which there are feweratoms of M^(A) than M^(B).

As used herein, the expression M^(A) is enriched, or M^(A) is enrichedrelative to M^(B) refers to a composition or formula in which there aremore atoms of M^(A) than M^(B).

As shown in Reaction Scheme 11, a polymeric precursor having theempirical formula M^(A) _(x)(M^(B1) _(1-y)M^(B2)_(y))_(v)((S_(1-z)Se_(z))R)_(w) may be formed using the mixture ofmonomers M^(B1)(ER)₃, M^(B2)(ER)₃ and M^(A)(ER).

where w can be (3v+x).

In some embodiments, a precursor compound may be a combination ofu*(1−x) equivalents of M^(A1)(ER), u*x equivalents of M^(A2)(ER),v*(1−y−t) equivalents of M^(B1)(ER)₃, v*y equivalents of M^(B2)(ER)₃,v*t equivalents of M^(B3)(ER)₃, wherein M^(A1) is Cu and M^(A2) is Ag,M^(B1), M^(B2) and M^(B3) are different atoms of Group 13, wherein thecompound has the empirical formula M^(A1) _(1-x)M^(A2) _(x))_(u)(M^(B1)_(1-y-t)M^(B2) _(y)M^(B3) _(t))_(v)((S_(1-z)Se_(z))R)_(w), wherein x isfrom 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum of y plus t isfrom 0 to 1, z is from 0 to 1, u is from 0.5 to 1.5, v is from 0.5 to1.5, w is from 2 to 6, and R represents R groups, of which there are win number, independently selected from alkyl, aryl, heteroaryl, alkenyl,amido, silyl, and inorganic and organic ligands.

In some embodiments, a precursor compound may have the empirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y-t)Ga_(y)Al_(t))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum ofy plus t is from 0 to 1, z is from 0 to 1, u is from 0.5 to 1.5, v isfrom 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of whichthere are w in number, as defined above.

In some embodiments, a precursor compound may have the empirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y-t)Ga_(y)Al_(t))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum ofy plus t is from 0 to 1, z is from 0 to 1, u is from 0.7 to 1.25, v isfrom 0.7 to 1.25, w is from 2 to 6, and R represents R groups, of whichthere are w in number, as defined above.

In some embodiments, a precursor compound may have the empirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y-t)Ga_(y)Al_(t))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum ofy plus t is from 0 to 1, z is from 0 to 1, u is from 0.8 to 0.95, v isfrom 0.9 to 1.1, w is from 3.6 to 4.4, and R represents R groups, ofwhich there are w in number, as defined above.

In some embodiments, a precursor compound may be a combination ofw*(1−z) equivalents of M^(A1)(ER¹), w*z equivalents of M^(A2)(ER²), xequivalents of M^(B1)(ER³)₃, y equivalents of M^(B2)(ER⁴)₃, tequivalents of M^(B3)(ER⁵)₃, wherein M^(A1) is Cu and M^(A2) is Ag,M^(B1), M^(B2) and M^(B3) are different atoms of Group 13, wherein thecompound has the empirical formula(Cu_(1-z)Ag_(z))_(w)In_(x)Ga_(y)Al_(t)(ER¹)_(w(1-z))(ER²)_((w*z))(ER³)_(3x)(ER⁴)_(3y)(ER⁵)_(3t),w is from 0.5 to 1.5, z is from 0 to 1, x is from 0 to 1, y is from 0 to1, t is from 0 to 1, x plus y plus t is one, and wherein R¹, R², R³, R⁴and R⁵ are the same or each different, and are independently selected,for each occurrence, from alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands.

In some embodiments, a precursor compound may have the empirical formula(Cu_(1-z)Ag_(z))_(w)In_(x)Ga_(y)Al_(t)(ER¹)_(w(1-z))(ER²)_((w*z))(ER³)_(3x)(ER⁴)_(3y)(ER⁵)_(3t),w is from 0.5 to 1.5, z is from 0 to 1, x is from 0 to 1, y is from 0 to1, t is from 0 to 1, x plus y plus t is one, and wherein R¹, R², R³, R⁴and R⁵ are as defined above.

In some embodiments, a precursor compound may have the empirical formula(Cu_(1-z)Ag_(z))_(w)In_(x)Ga_(y)Al_(t)(ER¹)_(w(1-z))(ER²)_((w*z))(ER³)_(3x)(ER⁴)_(3y)(ER⁵)_(3t),w is from 0.7 to 1.25, z is from 0 to 1, x is from 0 to 1, y is from 0to 1, t is from 0 to 1, x plus y plus t is one, and wherein R¹, R², R³,R⁴ and R⁵ are as defined above.

In some embodiments, a precursor compound may have the empirical formula(Cu_(1-z)Ag_(z))_(w)In_(x)Ga_(y)Al_(t)(ER¹)_(w(1-z))(ER²)_((w*z))(ER³)_(3x)(ER⁴)_(3y)(ER⁵)_(3t),w is from 0.8 to 0.95, z is from 0 to 1, x is from 0 to 1, y is from 0to 1, t is from 0 to 1, x plus y plus t is one, and wherein R¹, R², R³,R⁴ and R⁵ are as defined above.

In further aspects, a mixture of polymeric precursor compounds mayadvantageously be prepared with any desired stoichiometry of the numberof different metal atoms and atoms of Group 13 and their respectivestoichiometric levels or ratios.

As shown in Reaction Scheme 12, a polymeric precursor compound may beprepared by contacting x equivalents of M^(B1)(ER¹)₃, y equivalents ofM^(B2)(ER²)₃, and z equivalents of M^(A)(ER³), where M^(B1) and M^(B2)are different atoms of Group 13, x is from 0.5 to 1.5, y is from 0.5 to1.5, and z is from 0.5 to 1.5. For example, M^(B1) may be In and M^(B2)may be Ga.

A polymeric precursor compound may have the empirical formulaCu_(x)In_(y)Ga_(z)(ER¹)_(x)(ER²)_(3y)(ER³)_(3z), where R¹, R² and R³ arethe same or each different from the other. A polymeric precursorcompound of this kind can be used to control the ratio of In to Ga, andmake the ratio In:Ga a predetermined value.

Controlling the Stoichiometry of Monovalent Metal Atoms M^(A)

In some aspects, a polymeric precursor composition may advantageously beprepared with any desired stoichiometry of monovalent metal atoms M^(A).

Embodiments of this invention can provide polymeric precursor compoundsthat may advantageously be prepared with any desired stoichiometry withrespect to the number of different monovalent metal elements and theirrespective ratios. Polymeric precursor compounds having predeterminedstoichiometry may be used in a process for making a photovoltaicabsorber layer having the same predetermined stoichiometry on asubstrate. Processes for making a photovoltaic absorber layer havingpredetermined stoichiometry on a substrate include depositing aprecursor having the predetermined stoichiometry onto the substrate andconverting the deposited precursor into a photovoltaic absorbermaterial.

In some embodiments, a polymeric precursor can be made with apredetermined stoichiometry of Cu atoms. The amount of Cu relative toatoms of Group 13 can be a deficiency of copper, in which the ratio ofCu/In, Cu/Ga, Cu/(In+Ga), or Cu/(In+Ga+Al) is less than one. The amountof Cu relative to atoms of Group 13 can reflect enrichment of copper, inwhich the ratio of Cu/In, Cu/Ga, Cu/(In+Ga), or Cu/(In+Ga+Al) is greaterthan one.

In some embodiments, a polymeric precursor can be made with apredetermined stoichiometry of Ag atoms. The amount of Ag relative toatoms of Group 13 can be a deficiency of silver, in which the ratio ofAg/In, Ag/Ga, Ag/(In+Ga), or Ag/(In+Ga+Al) is less than one. The amountof Ag relative to atoms of Group 13 can reflect enrichment of silver, inwhich the ratio of Ag/In, Ag/Ga, Ag/(In+Ga), or Ag/(In+Ga+Al) is greaterthan one.

In some embodiments, a polymeric precursor can be made with apredetermined stoichiometry of Cu and Ag atoms. The amount of Cu and Agrelative to atoms of Group 13 can be a deficiency of copper and silver,in which the ratio of (Cu+Ag)/In, (Cu+Ag)/Ga, (Cu+Ag)/(In+Ga), or(Cu+Ag)/(In+Ga+Al) is less than one.

In some embodiments, the amount of Cu and Ag relative to atoms of Group13 can reflect enrichment of copper and silver, in which the ratio of(Cu+Ag)/In, (Cu+Ag)/Ga, (Cu+Ag)/(In+Ga), or (Cu+Ag)/(In+Ga+Al) isgreater than one.

In further embodiments, a polymeric precursor can be made with apredetermined stoichiometry of Cu to Ag atoms where the precursor hasany ratio of Cu to Ag. The ratio of Cu to Ag can be from about zero,where the precursor contains little or zero copper, to a very highratio, where the precursor contains little or zero silver.

In some aspects, polymeric precursor compounds of this invention havingpredetermined stoichiometry can be used to make photovoltaic materialshaving the stoichiometry of CIS, CIGS, AIS, AIGS, CAIS, CAIGS, orCAIGAS.

A precursor compound of this disclosure may be a combination of u*(1−x)equivalents of M^(A1)(ER), u*x equivalents of M^(A2)(ER), v*(1−y)equivalents of M^(B1)(ER)₃, v*y equivalents of M^(B2)(ER)₃, whereinM^(A1) is Cu and M^(A2) is Ag, M^(B1) and M^(B2) are different atoms ofGroup 13, wherein the compound has the empirical formula (M^(A1)_(1-x)M^(A2) _(x))_(u)(M^(B1) _(1-y)M^(B2)_(y))_(v)((S_(1-z)Se_(z))R)_(w), wherein x is from 0 to 1, y is from 0to 1, z is from 0 to 1, u is from 0.5 to 1.5, v is from 0.5 to 1.5, w isfrom 2 to 6, and R represents R groups, of which there are w in number,independently selected from alkyl, aryl, heteroaryl, alkenyl, amido,silyl, and inorganic and organic ligands. In these embodiments, aprecursor compound can have the stoichiometry useful to prepare CAIGS,CIGS and AIGS materials, including materials deficient in the quantityof a Group 11 atom.

In some embodiments, a precursor compound can be a combination ofw*(1−z) equivalents of M^(A1)(ER¹), w*z equivalents of M^(A2)(ER²), xequivalents of M^(B1)(ER³)₃, y equivalents of M^(B2)(ER⁴)₃, whereinM^(A1) is Cu and M^(A2) is Ag, M^(B1) and M^(B2) are different atoms ofGroup 13, wherein the compound has the empirical formula(Cu_(1-z)Ag_(z))_(w)In_(x)Ga_(y)(ER¹)_(w(1-z))(ER²)_((w*z))(ER³)_(3x)(ER⁴)_(3y),w is from 0.5 to 1.5, z is from 0 to 1, x is from 0 to 1, y is from 0 to1, x plus y is one, and wherein R¹, R², R³, R⁴ are the same or eachdifferent, and are independently selected, for each occurrence, fromalkyl, aryl, heteroaryl, alkenyl, amido, silyl, and inorganic andorganic ligands. In these embodiments, a precursor compound can have thestoichiometry useful to prepare CAIGS, CIGS and AIGS materials,including materials deficient in the quantity of a Group 11 atom.

A precursor compound of this disclosure may be a combination of xequivalents of M^(A1)(ER), v*(1−y) equivalents of M^(B1)(ER)₃, v*yequivalents of M^(B2)(ER)₃, wherein M^(A1) is Cu, M^(B1) and M^(B2) aredifferent atoms of Group 13, wherein the compound has the empiricalformula M^(A1) _(x)(M^(B1) _(1-y)M^(B2) _(y))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0.5 to 1.5, y is from 0 to 1, z is from 0 to 1, v isfrom 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of whichthere are w in number, independently selected from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands. Inthese embodiments, a precursor compound can have the stoichiometryuseful to prepare CIS or CIGS materials, including materials deficientor enriched in the quantity of a Group 11 atom.

In some embodiments, a precursor compound can be a combination of zequivalents of M^(A1)(ER¹), x equivalents of M^(B1)(ER²)₃, y equivalentsof M^(B2)(ER³)₃, wherein M^(A1) is Cu, M^(B1) and M^(B2) are differentatoms of Group 13, wherein the compound has the empirical formulaCu_(z)In_(x)Ga_(y)(ER¹)_(z)(ER²)_(3x)(ER³)_(3y), z is from 0.5 to 1.5, xis from 0 to 1, y is from 0 to 1, x plus y is one, and wherein R¹, R²,R³ are the same or each different, and are independently selected, foreach occurrence, from alkyl, aryl, heteroaryl, alkenyl, amido, silyl,and inorganic and organic ligands. In these embodiments, a precursorcompound can have the stoichiometry useful to prepare CIS or CIGSmaterials, including materials deficient or enriched in the quantity ofa Group 11 atom.

As shown in Reaction Scheme 13, a polymeric precursor compound may beprepared by contacting x equivalents of M^(A1)(ER¹), y equivalents ofM^(A2)(ER²), and z equivalents of M^(B)(ER³)₃, where M^(A1) and M^(A2)are different monovalent metal atoms, x is from 0.5 to 1.5, y is from0.5 to 1.5, and z is from 0.5 to 1.5. For example, M^(A1) may be Cu andM^(A2) may be Ag.

A polymeric precursor compound may have the empirical formulaCu_(x)Ag_(y)In_(z)(ER¹)_(x)(ER²)_(y)(ER³)_(3z), where R¹, R² and R³ arethe same or each different from the other. A polymeric precursorcompound of this kind can be used to control the ratio of Cu to Ag, andmake the ratio Cu:Ag a predetermined value.

Controlling the Stoichiometry of Atoms of Group 13 in a Thin FilmMaterial Made with a Polymeric Precursor

Embodiments of this invention can provide polymeric precursor compoundsthat may advantageously be prepared with any desired stoichiometry withrespect to the number of different Group 13 elements and theirrespective ratios. Polymeric precursor compounds having predeterminedstoichiometry may be used in a process for making a photovoltaicabsorber layer having the same predetermined stoichiometry on asubstrate. Processes for making a photovoltaic absorber layer havingpredetermined stoichiometry on a substrate include depositing aprecursor having the predetermined stoichiometry onto the substrate andconverting the deposited precursor into a photovoltaic absorbermaterial.

In some aspects, polymeric precursor compounds of this invention havingpredetermined stoichiometry can be used to make photovoltaic materialshaving the stoichiometry of CIGS, AIGS, CAIGS, CIGAS, AIGAS and CAIGAS.

In certain embodiments, the precursor may have predeterminedstoichiometry according to the empirical formula (M^(A1) _(1-x)M^(A2)_(x))_(u)(M^(B1) _(1-y-t)M^(B2) _(y)M^(B3)_(t))_(v)((S_(1-z)Se_(z))R)_(w), wherein x is from 0 to 1, y is from 0to 1, t is from 0 to 1, the sum of y plus t is from 0 to 1, z is from 0to 1, u is from 0.5 to 1.5, v is from 0.5 to 1.5, w is from 2 to 6, andR represents R groups, of which there are w in number, independentlyselected from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, andinorganic and organic ligands.

In further variations, the precursor can have predeterminedstoichiometry according to the empirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y-t)Ga_(y)Al_(t))_(v)((S_(1-z)Se_(z))R)_(w),wherein x is from 0 to 1, y is from 0 to 1, t is from 0 to 1, the sum ofy plus t is from 0 to 1, z is from 0 to 1, u is from 0.5 to 1.5, v isfrom 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of whichthere are w in number, independently selected from alkyl, aryl,heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands.

In some aspects, polymeric precursors having predetermined stoichiometrycan be used to make photovoltaic materials including CuGaS₂, AgGaS₂,AuGaS₂, CuInS₂, AgInS₂, AuInS₂, CuGaSe₂, AgGaSe₂, AuGaSe₂, CuInSe₂,AgInSe₂, AuInSe₂, CuGaTe₂, AgGaTe₂, AuGaTe₂, CuInTe₂, AgInTe₂, AuInTe₂,CuInGaSSe, AgInGaSSe, AuInGaSSe, CuInGaSSe, AgInGaSeTe, AuInGaSeTe,CuInGaSTe, AgInGaSTe, AuInGaSTe.

Controlling the Stoichiometry of Chalcogen Atoms in a Thin Film MaterialMade with a Polymeric Precursor

Embodiments of this invention may further provide methods forcontrolling the stoichiometry of chalcogen atoms and their respectiveratios.

In some embodiments, a mixture of polymeric precursor compounds mayadvantageously be prepared with any desired stoichiometry with respectto chalcogen atoms and their respective ratios. For example, in certainembodiments, a mixture of two or more polymeric precursor compounds maybe made from one or more precursor compounds that contain only sulfur,mixed with one or more different precursor compounds that contain onlyselenium.

Polymeric precursor compounds having predetermined chalcogenstoichiometry may be used in a process for making a photovoltaicabsorber layer having the same predetermined chalcogen stoichiometry ona substrate. Processes for making a photovoltaic absorber layer havingpredetermined stoichiometry on a substrate include depositing aprecursor having the predetermined stoichiometry onto the substrate andconverting the deposited precursor into a photovoltaic absorbermaterial.

Crosslinking Polymeric Precursors

Embodiments of this invention encompass methods and compositions forcrosslinking polymeric precursors and compositions.

In some aspects, a crosslinked polymeric precursor may be used tocontrol the viscosity of a precursor composition, or a polymericprecursor ink composition. The crosslinking of a polymeric precursor canincrease its molecular weight. The molecular weight of a polymericprecursor can be varied over a wide range by incorporating crosslinkinginto the preparation of the precursor. The viscosity of an inkcomposition can be varied over a wide range by using a crosslinkedprecursor to prepare an ink composition.

In some embodiments, the crosslinking of a polymeric precursorcomposition may be used to control the viscosity of the composition, orof a polymeric precursor ink composition. A polymeric precursorcomponent of a composition can be crosslinked by adding a crosslinkingagent to the composition. The viscosity of an ink composition may bevaried over a wide range by adding a crosslinking agent to the inkcomposition.

In further aspects, the crosslinking of a polymeric precursorcomposition may be used to control the variation of properties of thinfilms made with the precursor.

Examples of a crosslinking agent include E(Si(CH₃)₃)₂, where E is asdefined above.

Examples of a crosslinking agent include HEREH, M^(A)(ERE)H andM^(A)(ERE)M^(A), where M^(A), E, and R are as defined above.

A crosslinking agent can be made by reacting Cu₂O with HEREH to formCu(ERE)H or Cu(ERE)Cu.

Examples of a crosslinking agent include dithiols and diselenols, forexample, HER′EH, where E and R are as defined above. A diselenol canreact with two ER groups of different polymeric precursor chains to linkthe chains together.

An example of crosslinking using HER′EH is shown in Reaction Scheme 14.In Reaction Scheme 14, two chains of a polymeric precursor are linked bythe diselenol with elimination of 2 HER.

In another example, Cu(ER′E)Cu can be used during synthesis of apolymeric precursor to form crosslinks.

Embodiments of this invention may further provide a crosslinking agenthaving the formula (RE)₂M¹³(ER′E)M¹³(ER)₂, where M¹³, E, R′ and R are asdefined above. A crosslinking agent of this kind may be used eitherduring synthesis of a polymeric precursor to form crosslinks, or information of an ink or other composition.

In some embodiments, a polymeric precursor may incorporate crosslinkablefunctional groups. A crosslinkable functional group may be attached to aportion of the R groups of one or more kinds in the polymeric precursor.

Examples of crosslinkable functional groups include vinyl,vinylacrylate, epoxy, and cycloaddition and Diels-Alder reactive pairs.Crosslinking may be performed by methods known in the art including theuse of heat, light or a catalyst, as well as by vulcanization withelemental sulfur.

Dopants

In some embodiments, a polymeric precursor composition may include adopant. A dopant may be introduced into a polymeric precursor in thesynthesis of the precursor, or alternatively, can be added to acomposition or ink containing the polymeric precursor. A semiconductormaterial or thin film of this disclosure made from a polymeric precursormay contain atoms of one or more dopants. Methods for introducing adopant into a photovoltaic absorber layer include preparing the absorberlayer with a polymeric precursor of this invention containing thedopant.

The quantity of a dopant in an embodiment of this disclosure can be fromabout 1×10⁻⁷ atom percent to about 5 atom percent relative to the mostabundant Group 11 atom, or greater. In some embodiments, a dopant can beincluded at a level of from about 1×10¹⁶ cm⁻³ to about 1×10²¹ cm⁻³. Adopant can be included at a level of from about 1 ppm to about 10,000ppm.

In some embodiments, a dopant may be an alkali metal atom including Li,Na, K, Rb, and a mixture of any of the foregoing.

Embodiments of this invention may further include a dopant being analkaline earth metal atom including Be, Mg, Ca, Sr, Ba, and a mixture ofany of the foregoing.

In some embodiments, a dopant may be a transition metal atom from Group3 through Group 12.

In some embodiments, a dopant may be a transition metal atom from Group5 including V, Nb, Ta, and a mixture of any of the foregoing.

In some embodiments, a dopant may be a transition metal atom from Group6 including Cr, Mo, W, and a mixture of any of the foregoing.

In some embodiments, a dopant may be a transition metal atom from Group10 including Ni, Pd, Pt, and a mixture of any of the foregoing.

In some embodiments, a dopant may be a transition metal atom from Group12 including Zn, Cd, Hg, and a mixture of any of the foregoing.

In some embodiments, a dopant may be an atom from Group 14 including C,Si, Ge, Sn, Pb, and a mixture of any of the foregoing.

In some embodiments, a dopant may be an atom from Group 15 including P,As, Sb, Bi, and a mixture of any of the foregoing.

In some aspects, a polymeric precursor composition may advantageously beprepared to incorporate alkali metal ions as dopants. For example, apolymeric precursor composition may be prepared using an amount ofNa(ER), where E is S or Se and R is alkyl or aryl. In certainembodiments, a polymeric precursor composition may be prepared using anamount of NaIn(ER)₄, NaGa(ER)₄, LiIn(ER)₄, LiGa(ER)₄, KIn(ER)₄,KGa(ER)₄, or mixtures thereof, where E is S or Se and R is alkyl oraryl. A polymeric precursor compound of this kind can be used to controlthe level of alkali metal ions.

A dopant may be provided in a precursor as a counterion or introducedinto a thin film by any of the deposition methods described herein. Adopant may also be introduced into a thin film by methods known in theart including ion implantation.

A dopant of this disclosure may be p-type or n-type.

Any of the foregoing dopants may be used in an ink of this invention.

Capping Compounds

In some embodiments, a polymeric precursor composition may be formed asshown in Reaction Schemes 1 through 6, where one or more cappingcompounds are added to the reactions. A capping compound may control theextent of polymer chain formation. A capping compound may also be usedto control the viscosity of an ink containing the polymeric precursorcompound or composition, as well as its solubility and ability to from asuspension. Examples of capping compounds include inorganic ororganometallic complexes which bind to repeating units A or B, or both,and prevent further chain propagation. Examples of capping compoundsinclude R₂M^(B)ER, and RM^(B)(ER)₂.

Ligands

As used herein, the term ligand refers to any atom or chemical moietythat can donate electron density in bonding or coordination.

A ligand can be monodentate, bidentate or multidentate.

As used herein, the term ligand includes Lewis base ligands.

As used herein, the term organic ligand refers to an organic chemicalgroup composed of atoms of carbon and hydrogen, having from 1 to 22carbon atoms, and optionally containing oxygen, nitrogen, sulfur orother atoms, which can bind to another atom or molecule through a carbonatom. An organic ligand can be branched or unbranched, substituted orunsubstituted.

As used herein, the term inorganic ligand refers to an inorganicchemical group which can bind to another atom or molecule through anon-carbon atom.

Examples of ligands include halogens, water, alcohols, ethers,hydroxyls, amides, carboxylates, chalcogenylates, thiocarboxylates,selenocarboxylates, tellurocarboxylates, carbonates, nitrates,phosphates, sulfates, perchlorates, oxalates, and amines.

As used herein, the term chalcogenylate refers to thiocarboxylate,selenocarboxylate, and tellurocarboxylate, having the formula RCE₂ ⁻,where E is S, Se, or Te.

As used herein, the term chalcocarbamate refers to thiocarbamate,selenocarbamate, and tellurocarbamate, having the formula R¹R²NCE₂ ⁻,where E is S, Se, or Te, and W and R² are the same or different and arehydrogen, alkyl, aryl, or an organic ligand.

Examples of ligands include F⁻, Cl⁻, H₂O, ROH, R₂O, OH⁻, RO⁻, NR₂ ⁻,RCO₂ ⁻, RCE₂ ⁻, CO₃ ²⁻, NO₃ ⁻, PO₄ ³⁻, SO₄ ²⁻, ClO₄ ⁻, C₂O₄ ²⁻, NH₃,NR₃, R₂NH, and RNH₂, where R is alkyl, and E is chalcogen.

Examples of ligands include azides, heteroaryls, thiocyanates,arylamines, arylalkylamines, nitrites, and sulfites.

Examples of ligands include Br⁻, N₃ ⁻, pyridine, [SCN—]⁻, ArNH₂, NO₂ ⁻,and SO₃ ²⁻ where Ar is aryl.

Examples of ligands include cyanides or nitriles, isocyanides orisonitriles, alkylcyanides, alkylnitriles, alkylisocyanides,alkylisonitriles, arylcyanides, arylnitriles, arylisocyanides, andarylisonitriles.

Examples of ligands include hydrides, carbenes, carbon monoxide,isocyanates, isonitriles, thiolates, alkylthiolates, dialkylthiolates,thioethers, thiocarbamates, phosphines, alkylphosphines, arylphosphines,arylalkylphosphines, arsenines, alkylarsenines, arylarsenines,arylalkylarsenines, stilbines, alkylstilbines, arylstilbines, andarylalkylstilbines.

Examples of ligands include I⁻, H⁻, R⁻, —CN⁻, —CO, RNC, RSH, R₂S, RS⁻,—SCN⁻, R₃P, R₃As, R₃Sb, alkenes, and aryls, where each R isindependently alkyl, aryl, or heteroaryl.

Examples of ligands include trioctylphosphine, trimethylvinylsilane andhexafluoroacetylacetonate.

Examples of ligands include nitric oxide, silyls, alkylgermyls,arylgermyls, arylalkylgermyls, alkylstannyls, arylstannyls,arylalkylstannyls, selenocyanates, selenolates, alkylselenolates,dialkylselenolates, selenoethers, selenocarbamates, tellurocyanates,tellurolates, alkyltellurolates, dialkyltellurolates, telluroethers, andtellurocarbamates.

Examples of ligands include chalcogenates, thiothiolates,selenothiolates, thioselenolates, selenoselenolates, alkylthiothiolates, alkyl selenothiolates, alkyl thioselenolates, alkylselenoselenolates, aryl thiothiolates, aryl selenothiolates, arylthioselenolates, aryl selenoselenolates, arylalkyl thiothiolates,arylalkyl selenothiolates, arylalkyl thioselenolates, and arylalkylselenoselenolates.

Examples of ligands include selenoethers and telluroethers.

Examples of ligands include NO, O²⁻, NH_(n)R_(3-n), PH_(n)R_(3-n), SiR₃⁻, GeR₃ ⁻, SnR₃ ⁻, ⁻SR, ⁻SeR, ⁻TeR, ⁻SSR, ⁻SeSR, ⁻SSeR, ⁻SeSeR, and RCN,where n is from 1 to 3, and each R is independently alkyl or aryl.

As used herein, the term transition metals refers to atoms of Groups 3though 12 of the Periodic Table of the elements recommended by theCommission on the Nomenclature of Inorganic Chemistry and published inIUPAC Nomenclature of Inorganic Chemistry, Recommendations 2005.

Photovoltaic Absorber Layer Compositions

A polymeric precursor may be used to prepare a material for use indeveloping semiconductor products.

The polymeric precursors of this invention may advantageously be used inmixtures to prepare a material with controlled or predeterminedstoichiometric ratios of the metal atoms in the material.

In some aspects, processes for solar cells that avoid additionalsulfurization or selenization steps may advantageously use polymericprecursor compounds and compositions of this invention.

A polymeric precursor may be used to prepare an absorber material for asolar cell product. The absorber material may have the empirical formulaM^(A) _(x)(M^(B) _(1-y)M^(C) _(y))_(v)(E¹ _(1-z)E² _(z))_(w), whereM^(A) is a Group 11 atom selected from Cu, Ag, and Au, M^(B) and M^(C)are different Group 13 atoms selected from Al, Ga, In, Tl, or acombination thereof, E¹ is S or Se, E² is Se or Te, E¹ and E² aredifferent, x is from 0.5 to 1.5, y is from 0 to 1, and z is from 0 to 1,v is from 0.5 to 1.5, and w is from 1.5 to 2.5.

The absorber material may be either an n-type or a p-type semiconductor,when such compound is known to exist.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CIS layer on a substrate, wherein the layer has theempirical formula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.5to 1.5, y is from 0.5 to 1.5, z is from 0 to 1, and w is from 1.5 to2.5.

In some aspects, one or more polymeric precursor compounds may be usedto prepare a CIS layer on a substrate, wherein the layer has theempirical formula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.7to 1.2, y is from 0.7 to 1.2, z is from 0 to 1, and w is from 1.5 to2.5.

In some variations, one or more polymeric precursor compounds may beused to prepare a CIS layer on a substrate, wherein the layer has theempirical formula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.7to 1.1, y is from 0.7 to 1.1, z is from 0 to 1, and w is from 1.5 to2.5.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIS layer on a substrate, wherein the layer has theempirical formula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.8to 0.95, y is from 0.95 to 1.05, z is from 0 to 1, and w is from 1.8 to2.2.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIS layer on a substrate, wherein the layer has theempirical formula Cu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.8to 0.95, y is from 0.95 to 1.05, z is from 0 to 1, and w is from 2.0 to2.2.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.5 to 1.5, y is from 0 to 1, and z is from 0 to 1, v is from0.5 to 1.5, and w is from 1.5 to 2.5.

In some aspects, one or more polymeric precursor compounds may be usedto prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.7 to 1.2, y is from 0 to 1, and z is from 0 to 1, v is from0.7 to 1.2, and w is from 1.5 to 2.5.

In some variations, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.7 to 1.1, y is from 0 to 1, and z is from 0 to 1, v is from0.7 to 1.1, and w is from 1.5 to 2.5.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.7 to 1.1, y is from 0 to 1, and z is from 0 to 1, v is from0.7 to 1.1, and w is from 1.5 to 2.5.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.8 to 0.95, y is from 0 to 0.5, and z is from 0 to 1, v is from0.95 to 1.05, and w is from 1.8 to 2.2.

In certain embodiments, one or more polymeric precursor compounds may beused to prepare a CIGS layer on a substrate, wherein the layer has theempirical formula Cu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where xis from 0.8 to 0.95, y is from 0 to 0.5, and z is from 0 to 1, v is from0.95 to 1.05, and w is from 2.0 to 2.2.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CAIGS layer on a substrate, wherein the layer has theempirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where x isfrom 0.001 to 0.999, y is from 0 to 1, z is from 0 to 1, u is from 0.5to 1.5, v is from 0.5 to 1.5, and w is from 1.5 to 2.5.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CAIGS layer on a substrate, wherein the layer has theempirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where x isfrom 0.001 to 0.999, y is from 0 to 1, z is from 0 to 1, u is from 0.7to 1.2, v is from 0.7 to 1.2, and w is from 1.5 to 2.5.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CAIGS layer on a substrate, wherein the layer has theempirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where x isfrom 0.001 to 0.999, y is from 0 to 1, z is from 0 to 1, u is from 0.7to 1.1, v is from 0.7 to 1.1, and w is from 1.5 to 2.5.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CAIGS layer on a substrate, wherein the layer has theempirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where x isfrom 0.001 to 0.999, y is from 0 to 1, z is from 0.5 to 1, u is from 0.7to 1.1, v is from 0.7 to 1.1, and w is from 1.5 to 2.5.

In some embodiments, one or more polymeric precursor compounds may beused to prepare a CAIGS layer on a substrate, wherein the layer has theempirical formula(Cu_(1-x)Ag_(x))_(u)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where x isfrom 0.001 to 0.999, y is from 0 to 1, z is from 0.5 to 1, u is from 0.8to 0.95, v is from 0.7 to 1.1, and w is from 1.5 to 2.5.

Embodiments of this invention may further provide polymeric precursorsthat can be used to prepare a CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS,AIGAS or CAIGAS material for a solar cell product.

In some aspects, one or more polymeric precursors may be used to preparea CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGAS material asa chemically and physically uniform layer.

In some variations, one or more polymeric precursors may be used toprepare a CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGASmaterial wherein the stoichiometry of the metal atoms of the materialcan be controlled.

In certain variations, one or more polymeric precursors may be used toprepare a CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGASmaterial using nanoparticles prepared with the polymeric precursors.

In certain embodiments, one or more polymeric precursors may be used toprepare a CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGASmaterial as a layer that may be processed at relatively low temperaturesto achieve a solar cell.

In some aspects, one or more polymeric precursors may be used to preparea CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGAS material asa photovoltaic layer.

In some variations, one or more polymeric precursors may be used toprepare a chemically and physically uniform semiconductor CIS, CIGS,AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGAS layer on a variety ofsubstrates, including flexible substrates.

Examples of an absorber material include CuGaS₂, AgGaS₂, AuGaS₂, CuInS₂,AgInS₂, AuInS₂, CuTlS₂, AgTlS₂, AuTlS₂, CuGaSe₂, AgGaSe₂, AuGaSe₂,CuInSe₂, AgInSe₂, AuInSe₂, CuTlSe₂, AgTlSe₂, AuTlSe₂, CuGaTe₂, AgGaTe₂,AuGaTe₂, CuInTe₂, AgInTe₂, AuInTe₂, CuTlTe₂, AgTlTe₂, and AuTlTe₂.

Examples of an absorber material include CuInGaSSe, AgInGaSSe,AuInGaSSe, CuInTlSSe, AgInTlSSe, AuInTlSSe, CuGaTlSSe, AgGaTlSSe,AuGaTlSSe, CuInGaSSe, AgInGaSeTe, AuInGaSeTe, CuInTlSeTe, AgInTlSeTe,AuInTlSeTe, CuGaTlSeTe, AgGaTlSeTe, AuGaTlSeTe, CuInGaSTe, AgInGaSTe,AuInGaSTe, CuInTlSTe, AgInTlSTe, AuInTlSTe, CuGaTlSTe, AgGaTlSTe, andAuGaTlSTe.

The CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGAS layer maybe used with various junction partners to produce a solar cell. Examplesof junction partner layers are known in the art and include CdS, ZnS,ZnSe, and CdZnS. See, for example, Martin Green, Solar Cells: OperatingPrinciples, Technology and System Applications (1986); Richard H. Bube,Photovoltaic Materials (1998); Antonio Luque and Steven Hegedus,Handbook of Photovoltaic Science and Engineering (2003).

In some aspects, the thickness of an absorber layer may be from about0.01 to about 100 micrometers, or from about 0.01 to about 20micrometers, or from about 0.01 to about 10 micrometers, or from about0.05 to about 5 micrometers, or from about 0.1 to about 4 micrometers,or from about 0.1 to about 3.5 micrometers, or from about 0.1 to about 3micrometers, or from about 0.1 to about 2.5 micrometers.

Substrates

The polymeric precursors of this invention can be used to form a layeron a substrate. The substrate can be made of any substance, and can haveany shape. Substrate layers of polymeric precursors can be used tocreate a photovoltaic layer or device.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include semiconductors, dopedsemiconductors, silicon, gallium arsenide, insulators, glass, molybdenumglass, silicon dioxide, titanium dioxide, zinc oxide, silicon nitride,and combinations thereof.

A substrate may be coated with molybdenum or a molybdenum-containingcompound.

In some embodiments, a substrate may be pre-treated with amolybdenum-containing compound, or one or more compounds containingmolybdenum and selenium.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include metals, metal foils, molybdenum,aluminum, beryllium, cadmium, cerium, chromium, cobalt, copper, gallium,gold, lead, manganese, nickel, palladium, platinum, rhenium, rhodium,silver, stainless steel, steel, iron, strontium, tin, titanium,tungsten, zinc, zirconium, metal alloys, metal silicides, metalcarbides, and combinations thereof.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include polymers, plastics, conductivepolymers, copolymers, polymer blends, polyethylene terephthalates,polycarbonates, polyesters, polyester films, mylars, polyvinylfluorides, polyvinylidene fluoride, polyethylenes, polyetherimides,polyethersulfones, polyetherketones, polyimides, polyvinylchlorides,acrylonitrile butadiene styrene polymers, silicones, epoxys, andcombinations thereof.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include roofing materials.

Examples of substrates on which a polymeric precursor of this disclosurecan be deposited or printed include papers and coated papers.

A substrate of this disclosure can be of any shape. Examples ofsubstrates on which a polymeric precursor of this disclosure can bedeposited include a shaped substrate including a tube, a cylinder, aroller, a rod, a pin, a shaft, a plane, a plate, a blade, a vane, acurved surface or a spheroid.

A substrate may be layered with an adhesion promoter before thedeposition, coating or printing of a layer of a polymeric precursor ofthis invention.

Examples of adhesion promoters include a glass layer, a metal layer, atitanium-containing layer, a tungsten-containing layer, atantalum-containing layer, tungsten nitride, tantalum nitride, titaniumnitride, titanium nitride silicide, tantalum nitride silicide, achromium-containing layer, a vanadium-containing layer, a nitride layer,an oxide layer, a carbide layer, and combinations thereof.

Examples of adhesion promoters include organic adhesion promoters suchas organofunctional silane coupling agents, silanes,hexamethyldisilazanes, glycol ether acetates, ethylene glycolbis-thioglycolates, acrylates, acrylics, mercaptans, thiols, selenols,tellurols, carboxylic acids, organic phosphoric acids, triazoles, andmixtures thereof.

Substrates may be layered with a barrier layer before the deposition ofprinting of a layer of a polymeric precursor of this invention.

Examples of a barrier layer include a glass layer, a metal layer, atitanium-containing layer, a tungsten-containing layer, atantalum-containing layer, tungsten nitride, tantalum nitride, titaniumnitride, titanium nitride silicide, tantalum nitride silicide, andcombinations thereof.

A substrate can be of any thickness, and can be from about 20micrometers to about 20,000 micrometers or more in thickness.

Ink Compositions

Embodiments of this invention further provide ink compositions whichcontain one or more polymeric precursor compounds. The polymericprecursors of this invention may be used to make photovoltaic materialsby printing an ink onto a substrate.

An ink of this disclosure advantageously allows precise control of thestoichiometric ratios of certain atoms in the ink because the ink can becomposed of a mixture of polymeric precursors.

Inks of this disclosure can be made by any methods known in the art.

In some embodiments, an ink can be made by mixing a polymeric precursorwith one or more carriers. The ink may be a suspension of the polymericprecursors in an organic carrier. In some variations, the ink is asolution of the polymeric precursors in an organic carrier. The carriercan include one or more organic liquids or solvents, and may contain anaqueous component.

An ink can be made by providing one or more polymeric precursorcompounds and solubilizing, dissolving, solvating, or dispersing thecompounds with one or more carriers. The compounds dispersed in acarrier may be nanocrystalline, nanoparticles, microparticles,amorphous, or dissolved molecules.

The concentration of the polymeric precursors in an ink of thisdisclosure can be from about 0.001% to about 99% (w/w), or from about0.001% to about 90%, or from about 0.1% to about 90%.

A polymeric precursor may exist in a liquid or flowable phase under thetemperature and conditions used for deposition, coating or printing.

In some variations of this invention, polymeric precursors that arepartially soluble, or are insoluble in a particular carrier can bedispersed in the carrier by high shear mixing.

As used herein, the term dispersing encompasses the terms solubilizing,dissolving, and solvating.

The carrier for an ink of this disclosure may be an organic liquid orsolvent. Examples of a carrier for an ink of this disclosure include oneor more organic solvents, which may contain an aqueous component.

Embodiments of this invention further provide polymeric precursorcompounds having enhanced solubility in one or more carriers forpreparing inks. The solubility of a polymeric precursor compound can beselected by variation of the nature and molecular size and weight of oneor more organic ligands attached to the compound.

An ink composition of this invention may contain any of the dopantsdisclosed herein, or a dopant known in the art.

Ink compositions of this disclosure can be made by methods known in theart, as well as methods disclosed herein.

Examples of a carrier for an ink of this disclosure include alcohol,methanol, ethanol, isopropyl alcohol, thiols, butanol, butanediol,glycerols, alkoxyalcohols, glycols, 1-methoxy-2-propanol, acetone,ethylene glycol, propylene glycol, propylene glycol laurate, ethyleneglycol ethers, diethylene glycol, triethylene glycol monobutylether,propylene glycol monomethylether, 1,2-hexanediol, ethers, diethyl ether,aliphatic hydrocarbons, aromatic hydrocarbons, pentane, hexane, heptane,octane, isooctane, decane, cyclohexane, p-xylene, m-xylene, o-xylene,benzene, toluene, xylene, tetrahydrofuran, 2-methyltetrahydrofuran,siloxanes, cyclosiloxanes, silicone fluids, halogenated hydrocarbons,dibromomethane, dichloromethane, dichloroethane, trichloroethanechloroform, methylene chloride, acetonitrile, esters, acetates, ethylacetate, butyl acetate, acrylates, isobornyl acrylate, 1,6-hexanedioldiacrylate, polyethylene glycol diacrylate, ketones, acetone, methylethyl ketone, cyclohexanone, butyl carbitol, cyclopentanone, lactams,N-methylpyrrolidone, N-(2-hydroxyethyl)-pyrrolidone, cyclic acetals,cyclic ketals, aldehydes, amides, dimethylformamide, methyl lactate,oils, natural oils, terpenes, and mixtures thereof.

An ink of this disclosure may further include components such as asurfactant, a dispersant, an emulsifier, an anti-foaming agent, a dryer,a filler, a resin binder, a thickener, a viscosity modifier, ananti-oxidant, a flow agent, a plasticizer, a conductivity agent, acrystallization promoter, an extender, a film conditioner, an adhesionpromoter, and a dye. Each of these components may be used in an ink ofthis disclosure at a level of from about 0.001% to about 10% or more ofthe ink composition.

Examples of surfactants include siloxanes, polyalkyleneoxide siloxanes,polyalkyleneoxide polydimethylsiloxanes, polyesterpolydimethylsiloxanes, ethoxylated nonylphenols, nonylphenoxypolyethyleneoxyethanol, fluorocarbon esters, fluoroaliphatic polymericesters, fluorinated esters, alkylphenoxy alkyleneoxides, cetyl trimethylammonium chloride, carboxymethylamylose, ethoxylated acetylene glycols,betaines, N-n-dodecyl-N,N-dimethylbetaine, dialkyl sulfosuccinate salts,alkylnaphthalenesulfonate salts, fatty acid salts, polyoxyethylenealkylethers, polyoxyethylene alkylallylethers,polyoxyethylene-polyoxypropylene block copolymers, alkylamine salts,quaternary ammonium salts, and mixtures thereof.

Examples of surfactants include anionic, cationic, amphoteric, andnonionic surfactants. Examples of surfactants include SURFYNOL, DYNOL,ZONYL, FLUORAD, and SILWET surfactants.

A surfactant may be used in an ink of this disclosure at a level of fromabout 0.001% to about 2% of the ink composition.

Examples of a dispersant include a polymer dispersant, a surfactant,hydrophilic-hydrophobic block copolymers, acrylic block copolymers,acrylate block copolymers, graft polymers, and mixtures thereof.

Examples of an emulsifier include a fatty acid derivative, an ethylenestearamide, an oxidized polyethylene wax, mineral oils, apolyoxyethylene alkyl phenol ether, a polyoxyethylene glycol ether blockcopolymer, a polyoxyethylene sorbitan fatty acid ester, a sorbitan, analkyl siloxane polyether polymer, polyoxyethylene monostearates,polyoxyethylene monolaurates, polyoxyethylene monooleates, and mixturesthereof.

Examples of an anti-foaming agent include polysiloxanes,dimethylpolysiloxanes, dimethyl siloxanes, silicones, polyethers, octylalcohol, organic esters, ethyleneoxide propyleneoxide copolymers, andmixtures thereof.

Examples of a dryer include aromatic sulfonic acids, aromatic carboxylicacids, phthalic acid, hydroxyisophthalic acid, N-phthaloylglycine,2-Pyrrolidone 5-carboxylic acid, and mixtures thereof.

Examples of a filler include metallic fillers, silver powder, silverflake, metal coated glass spheres, graphite powder, carbon black,conductive metal oxides, ethylene vinyl acetate polymers, and mixturesthereof.

Examples of a resin binder include acrylic resins, alkyd resins, vinylresins, polyvinyl pyrrolidone, phenolic resins, ketone resins, aldehyderesins, polyvinyl butyral resin, amide resins, amino resins,acrylonitrile resins, cellulose resins, nitrocellulose resins, rubbers,fatty acids, epoxy resins, ethylene acrylic copolymers, fluoropolymers,gels, glycols, hydrocarbons, maleic resins, urea resins, naturalrubbers, natural gums, phenolic resins, cresols, polyamides,polybutadienes, polyesters, polyolefins, polyurethanes, isocynates,polyols, thermoplastics, silicates, silicones, polystyrenes, andmixtures thereof.

Examples of thickeners and viscosity modifiers include conductingpolymers, celluloses, urethanes, polyurethanes, styrene maleic anhydridecopolymers, polyacrylates, polycarboxylic acids, carboxymethylcelluoses,hydroxyethylcelluloses, methylcelluloses, methyl hydroxyethylcelluloses, methyl hydroxypropyl celluloses, silicas, gellants,aluminates, titanates, gums, clays, waxes, polysaccharides, starches,and mixtures thereof.

Examples of anti-oxidants include phenolics, phosphites, phosphonites,thioesters, stearic acids, ascorbic acids, catechins, cholines, andmixtures thereof.

Examples of flow agents include waxes, celluloses, butyrates,surfactants, polyacrylates, and silicones.

Examples of a plasticizer include alkyl benzyl phthalates, butyl benzylphthalates, dioctyl phthalates, diethyl phthalates, dimethyl phthalates,di-2-ethylhexy-adipates, diisobutyl phthalates, diisobutyl adipates,dicyclohexyl phthalates, glycerol tribenzoates, sucrose benzoates,polypropylene glycol dibenzoates, neopentyl glycol dibenzoates, dimethylisophthalates, dibutyl phthalates, dibutyl sebacates,tri-n-hexyltrimellitates, and mixtures thereof.

Examples of a conductivity agent include lithium salts, lithiumtrifluoromethanesulfonates, lithium nitrates, dimethylaminehydrochlorides, diethylamine hydrochlorides, hydroxylaminehydrochlorides, and mixtures thereof.

Examples of a crystallization promoter include copper chalcogenides,alkali metal chalcogenides, alkali metal salts, alkaline earth metalsalts, sodium chalcogenates, cadmium salts, cadmium sulfates, cadmiumsulfides, cadmium selenides, cadmium tellurides, indium sulfides, indiumselenides, indium tellurides, gallium sulfides, gallium selenides,gallium tellurides, molybdenum, molybdenum sulfides, molybdenumselenides, molybdenum tellurides, molybdenum-containing compounds, andmixtures thereof.

An ink may contain one or more components selected from the group of aconducting polymer, silver metal, silver selenide, silver sulfide,copper metal, indium metal, gallium metal, zinc metal, alkali metals,alkali metal salts, alkaline earth metal salts, sodium chalcogenates,calcium chalcogenates, cadmium sulfide, cadmium selenide, cadmiumtelluride, indium sulfide, indium selenide, indium telluride, galliumsulfide, gallium selenide, gallium telluride, zinc sulfide, zincselenide, zinc telluride, copper sulfide, copper selenide, coppertelluride, molybdenum sulfide, molybdenum selenide, molybdenumtelluride, and mixtures of any of the foregoing.

An ink of this disclosure may contain particles of a metal, a conductivemetal, or an oxide. Examples of metal and oxide particles includesilica, alumina, titania, copper, iron, steel, aluminum and mixturesthereof.

In certain variations, an ink may contain a biocide, a sequesteringagent, a chelator, a humectant, a coalescent, or a viscosity modifier.

In certain aspects, an ink of this disclosure may be formed as asolution, a suspension, a slurry, or a semisolid gel or paste. An inkmay include one or more polymeric precursors solubilized in a carrier,or may be a solution of the polymeric precursors. In certain variations,a polymeric precursor may include particles or nanoparticles that can besuspended in a carrier, and may be a suspension or paint of thepolymeric precursors. In certain embodiments, a polymeric precursor canbe mixed with a minimal amount of a carrier, and may be a slurry orsemisolid gel or paste of the polymeric precursor.

The viscosity of an ink of this disclosure can be from about 0.5centipoises (cP) to about 50 cP, or from about 0.6 to about 30 cP, orfrom about 1 to about 15 cP, or from about 2 to about 12 cP.

The viscosity of an ink of this disclosure can be from about 20 cP toabout 2×10⁶ cP, or greater. The viscosity of an ink of this disclosurecan be from about 20 cP to about 1×10⁶ cP, or from about 200 cP to about200,000 cP, or from about 200 cP to about 100,000 cP, or from about 200cP to about 40,000 cP, or from about 200 cP to about 20,000 cP.

The viscosity of an ink of this disclosure can be about 1 cP, or about 2cP, or about 5 cP, or about 20 cP, or about 100 cP, or about 500 cP, orabout 1,000 cP, or about 5,000 cP, or about 10,000 cP, or about 20,000cP, or about 30,000 cP, or about 40,000 cP.

In some embodiments, an ink may contain one or more components from thegroup of a surfactant, a dispersant, an emulsifier, an anti-foamingagent, a dryer, a filler, a resin binder, a thickener, a viscositymodifier, an anti-oxidant, a flow agent, a plasticizer, a conductivityagent, a crystallization promoter, an extender, a film conditioner, anadhesion promoter, and a dye. In certain variations, an ink may containone or more compounds from the group of cadmium sulfide, cadmiumselenide, cadmium telluride, zinc sulfide, zinc selenide, zinctelluride, copper sulfide, copper selenide, and copper telluride. Insome aspects, an ink may contain particles of a metal, a conductivemetal, or an oxide.

An ink may be made by dispersing one or more polymeric precursorcompounds of this disclosure in one or more carriers to form adispersion or solution.

A polymeric precursor ink composition can be prepared by dispersing oneor more polymeric precursors in a solvent, and heating the solvent todissolve or disperse the polymeric precursors. The polymeric precursorsmay have a concentration of from about 0.001% to about 99% (w/w), orfrom about 0.001% to about 90%, or from about 0.1% to about 90%, or fromabout 0.1% to about 50%, or from about 0.1% to about 40%, or from about0.1% to about 30%, or from about 0.1% to about 20%, or from about 0.1%to about 10% in the solution or dispersion.

An ink composition may further contain an additional indium-containingcompound, or an additional gallium-containing compound. Examples ofadditional indium-containing compounds include In(SeR)₃, wherein R isalkyl or aryl. Examples of additional gallium-containing compoundsinclude Ga(SeR)₃, wherein R is alkyl or aryl. For example, an ink mayfurther contain In(Se^(n)Bu)₃ or Ga(Se^(n)Bu)₃, or mixtures thereof. Insome embodiments, an ink may contain Na(ER), where E is S or Se and R isalkyl or aryl. In certain embodiments, an ink may contain NaIn(ER)₄,NaGa(ER)₄, LiIn(ER)₄, LiGa(ER)₄, KIn(ER)₄, or KGa(ER)₄, where E is S orSe and R is alkyl or aryl.

Processes for Films of Polymeric Precursors on Substrates

The polymeric precursors of this invention can be used to makephotovoltaic materials by depositing a layer onto a substrate, where thelayer contains one or more polymeric precursors. The deposited layer maybe a film or a thin film. Substrates are described above.

As used herein, the terms “deposit,” “depositing,” and “deposition”refer to any method for placing a compound or composition onto a surfaceor substrate, including spraying, coating, and printing.

As used herein, the term “thin film” refers to a layer of atoms ormolecules, or a composition layer on a substrate having a thickness ofless than about 300 micrometers.

A deposited layer of this disclosure advantageously allows precisecontrol of the stoichiometric ratios of certain atoms in the layerbecause the layer can be composed of a mixture of polymeric precursors.

The polymeric precursors of this invention, and compositions containingpolymeric precursors, can be deposited onto a substrate using methodsknown in the art, as well as methods disclosed herein.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include all forms of spraying, coating, and printing.

Solar cell layers can be made by depositing one or more polymericprecursors of this disclosure on a flexible substrate in a highthroughput roll process. The depositing of polymeric precursors in ahigh throughput roll process can be done by spraying or coating acomposition containing one or more polymeric precursors, or by printingan ink containing one or more polymeric precursors of this disclosure.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include spraying, spray coating, spray deposition, spraypyrolysis, and combinations thereof.

Examples of methods for printing using an ink of this disclosure includeprinting, screen printing, inkjet printing, aerosol jet printing, inkprinting, jet printing, stamp/pad printing, transfer printing, padprinting, flexographic printing, gravure printing, contact printing,reverse printing, thermal printing, lithography, electrophotographicprinting, and combinations thereof.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include electrodepositing, electroplating, electrolessplating, bath deposition, coating, dip coating, wet coating, spincoating, knife coating, roller coating, rod coating, slot die coating,meyerbar coating, lip direct coating, capillary coating, liquiddeposition, solution deposition, layer-by-layer deposition, spincasting, and solution casting.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include chemical vapor deposition, aerosol chemical vapordeposition, metal-organic chemical vapor deposition, organometallicchemical vapor deposition, plasma enhanced chemical vapor deposition,and combinations thereof.

Examples of methods for depositing a polymeric precursor onto a surfaceor substrate include atomic layer deposition, plasma-enhanced atomiclayer deposition, vacuum chamber deposition, sputtering, RF sputtering,DC sputtering, magnetron sputtering, evaporation, electron beamevaporation, laser ablation, gas-source polymeric beam epitaxy, vaporphase epitaxy, liquid phase epitaxy, and combinations thereof.

In certain embodiments, a first polymeric precursor may be depositedonto a substrate, and subsequently a second polymeric precursor may bedeposited onto the substrate. In certain embodiments, several differentpolymeric precursors may be deposited onto the substrate to create alayer.

In certain variations, different polymeric precursors may be depositedonto a substrate simultaneously, or sequentially, whether by spraying,coating, printing, or by other methods. The different polymericprecursors may be contacted or mixed before the depositing step, duringthe depositing step, or after the depositing step. The polymericprecursors can be contacted before, during, or after the step oftransporting the polymeric precursors to the substrate surface.

The depositing of polymeric precursors, including by spraying, coating,and printing, can be done in a controlled or inert atmosphere, such asin dry nitrogen and other inert gas atmospheres, as well as in a partialvacuum atmosphere.

Processes for depositing, spraying, coating, or printing polymericprecursors can be done at various temperatures including from about −20°C. to about 650° C., or from about −20° C. to about 600° C., or fromabout −20° C. to about 400° C., or from about 20° C. to about 360° C.,or from about 20° C. to about 300° C., or from about 20° C. to about250° C.

Processes for making a solar cell involving a step of transforming apolymeric precursor compound into a material or semiconductor can beperformed at various temperatures including from about 100° C. to about650° C., or from about 150° C. to about 650° C., or from about 250° C.to about 650° C., or from about 300° C. to about 650° C., or from about400° C. to about 650° C., or from about 300° C. to about 600° C., orfrom about 300° C. to about 550° C., or from about 300° C. to about 500°C., or from about 300° C. to about 450° C.

In certain aspects, depositing of polymeric precursors on a substratecan be done while the substrate is heated. In these variations, athin-film material may be deposited or formed on the substrate.

In some embodiments, a step of converting a precursor to a material anda step of annealing can be done simultaneously. In general, a step ofheating a precursor can be done before, during or after any step ofdepositing the precursor.

In some variations, a substrate can be cooled after a step of heating.In certain embodiments, a substrate can be cooled before, during, orafter a step of depositing a precursor. A substrate may be cooled toreturn the substrate to a lower temperature, or to room temperature, orto an operating temperature of a deposition unit. Various coolants orcooling methods can be applied to cool a substrate.

The depositing of polymeric precursors on a substrate may be done withvarious apparatuses and devices known in art, as well as devicesdescribed herein.

In some variations, the depositing of polymeric precursors can beperformed using a spray nozzle with adjustable nozzle dimensions toprovide a uniform spray composition and distribution.

Embodiments of this disclosure further contemplate articles made bydepositing a layer onto a substrate, where the layer contains one ormore polymeric precursors. The article may be a substrate having a layerof a film, or a thin film, which is deposited, sprayed, coated, orprinted onto the substrate. In certain variations, an article may have asubstrate printed with a polymeric precursor ink, where the ink isprinted in a pattern on the substrate.

For spin coating, an ink can be made by dissolving a polymeric precursorin a solvent in an inert atmosphere glove box. The ink can be passedthrough a syringe filter and deposited onto a Mo-coated glass substratein a quantity sufficient to cover the entire substrate surface. Thesubstrate can be then spun at 1200 rpm for about 60 s. The coatedsubstrate can be allowed to dry at room temperature, typically for 1-2minutes. The coated substrate can be heated in a furnace for conversionof the polymeric molecular precursor film to a semiconductor thin filmmaterial.

Examples of thermal conversion include heating the coated substrate at110° C. for 15 min (10° C./min ramp) followed by heating at 260° C. for60 min (20° C./min ramp). Thermal conversion of the coated substrate canalso be done by placing it in a pre-heated (300° C.) furnace for 10 min,or 20 min, or 30 min, or longer.

After conversion of the coated substrate, another precursor coating maybe applied to the thin film material on the substrate by repeating theprocedure above. This process can be repeated to prepare additional thinfilm material layers on the substrate.

After the last thin film material layer is prepared on the substrate,the substrate can be annealed. The annealing process may include a stepof heating the coated substrate at a temperature sufficient to convertthe coating on the substrate to a thin film photovoltaic material. Theannealing process may include a step of heating the coated substrate at400° C. for 60 min (30° C./min ramp), or 500° C. for 30 min (30° C./minramp), or 550° C. for 60 min (10° C./min ramp), or 550° C. for 20 min(30° C./min ramp). The annealing process may include an additional stepof heating the coated substrate at 550° C. for 10 min (30° C./min ramp),or 525° C. for 10 min (20° C./s ramp), or 400° C. for 5 min (40° C./sramp).

Photovoltaic Devices

The polymeric precursors of this invention can be used to makephotovoltaic materials and solar cells of high efficiency.

Some standards for testing and performance of photovoltaic (PV) devicesare described by The National Renewable Energy Laboratory of the U.S.Department of Energy (DOE).

As shown in FIG. 6, embodiments of this invention may further provideoptoelectronic devices and energy conversion systems. Following thesynthesis of polymeric precursor compounds, the compounds can besprayed, deposited, or printed onto substrates and formed into absorbermaterials and semiconductor layers. Absorber materials can be the basisfor optoelectronic devices and energy conversion systems.

In some embodiments, the solar cell is a thin layer solar cell having aCIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGAS absorber layerdeposited or printed on a substrate.

Embodiments of this invention may provide improved efficiency for solarcells used for light to electricity conversion.

In some embodiments, a solar cell of this disclosure is a heterojunctiondevice made with a CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS orCAIGAS cell. The CIS, CIGS, AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS orCAIGAS layer may be used as a junction partner with a layer of, forexample, cadmium sulfide, cadmium selenide, cadmium telluride, zincsulfide, zinc selenide, or zinc telluride. The absorber layer may beadjacent to a layer of MgS, MgSe, MgTe, HgS, HgSe, HgTe, AlN, AlP, AlAs,AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, or combinationsthereof.

In certain variations, a solar cell of this disclosure is amultijunction device made with one or more stacked solar cells.

As shown in FIG. 7, a solar cell device of this disclosure may have asubstrate 10, an electrode layer 20, an absorber layer 30, a windowlayer 40, and a transparent conductive layer (TCO) 50. The substrate 10may be metal, plastic, glass, or ceramic. The electrode layer 20 can bea molybdenum-containing layer. The absorber layer 30 may be a CIS, CIGS,AIS, AIGS, CAIS, CAIGS, CIGAS, AIGAS or CAIGAS layer. The window layer40 may be a cadmium sulfide layer. The transparent conductive layer 50can be an indium tin oxide layer or a doped zinc oxide layer.

A solar cell device of this disclosure may have a substrate, anelectrode layer, an absorber layer, a window layer, an adhesionpromoting layer, a junction partner layer, a transparent layer, atransparent electrode layer, a transparent conductive oxide layer, atransparent conductive polymer layer, a doped conductive polymer layer,an encapsulating layer, an anti-reflective layer, a protective layer, ora protective polymer layer. In certain variations, an absorber layerincludes a plurality of absorber layers.

In certain variations, solar cells may be made by processes usingpolymeric precursor compounds and compositions of this invention thatadvantageously avoid additional sulfurization or selenization steps.

In certain variations, a solar cell device may have amolybdenum-containing layer, or an interfacial molybdenum-containinglayer.

Examples of a protective polymer include silicon rubbers, butyrylplastics, ethylene vinyl acetates, and combinations thereof.

Substrates can be made of a flexible material which can be handled in aroll. The electrode layer may be a thin foil.

Absorber layers of this disclosure can be made by depositing or printinga composition containing nanoparticles onto a substrate, where thenanoparticles can be made with polymeric precursor compounds of thisinvention. In some processes, nanoparticles can be made with polymericprecursor compounds and deposited on a substrate. Depositednanoparticles can subsequently be transformed by the application of heator energy.

In some embodiments, the absorber layer may be formed from nanoparticlesor semiconductor nanoparticles which have been deposited on a substrateand subsequently transformed by heat or energy.

In some embodiments, a thin film photovoltaic device may have atransparent conductor layer, a buffer layer, a p-type absorber layer, anelectrode layer, and a substrate. The transparent conductor layer may bea transparent conductive oxide (TCO) layer such as a zinc oxide layer,or zinc oxide layer doped with aluminum, or a carbon nanotube layer, ora tin oxide layer, or a tin oxide layer doped with fluorine, or anindium tin oxide layer, or an indium tin oxide layer doped withfluorine, while the buffer layer can be cadmium sulfide, or cadmiumsulfide and high resistivity zinc oxide. The p-type absorber layer canbe a CIGS layer, and the electrode layer can be molybdenum. Thetransparent conductor layer can be up to about 0.5 micrometers inthickness. The buffer layer can also be a cadmium sulfide n-typejunction partner layer. In some embodiments, the buffer layer may be asilicon dioxide, an aluminum oxide, a titanium dioxide, or a boronoxide.

Some examples of transparent conductive oxides are given in K. Ellmer etal., Transparent Conductive Zinc Oxide, Vol. 104, Springer Series inMaterials Science (2008).

In some aspects, a solar cell can include a molybdenum selenideinterface layer, which may be formed using various molybdenum-containingand selenium-containing compounds that can be added to an ink forprinting, or deposited onto a substrate.

A thin film material photovoltaic absorber layer can be made with one ormore polymeric precursors of this invention. For example, a polymericprecursor ink can be sprayed onto a stainless steel substrate using aspray pyrolysis unit in a glovebox in an inert atmosphere. The spraypyrolysis unit may have an ultrasonic nebulizer, precision flow metersfor inert gas carrier, and a tubular quartz reactor in a furnace. Thespray-coated substrate can be heated at a temperature of from about 25°C. to about 650° C. in an inert atmosphere, thereby producing a thinfilm material photovoltaic absorber layer.

In some examples, a thin film material photovoltaic absorber layer canbe made by providing a polymeric precursor ink which is filtered with a0.45 micron filter, or a 0.3 micron filter. The ink can be depositedonto an aluminum substrate using a spin casting unit in a glovebox ininert argon atmosphere. The substrate can be spin coated with thepolymeric precursor ink to a film thickness of about 0.1 to 5 microns.The substrate can be removed and heated at a temperature of from about100° C. to about 600° C., or from about 100° C. to about 650° C. in aninert atmosphere, thereby producing a thin film material photovoltaicabsorber layer.

In further examples, a thin film material photovoltaic absorber layercan be made by providing a polymeric precursor ink which is filteredwith a 0.45 micron filter, or a 0.3 micron filter. The ink may beprinted onto a polyethylene terephthalate substrate using a inkjetprinter in a glovebox in an inert atmosphere. A film of about 0.1 to 5microns thickness can be deposited on the substrate. The substrate canbe removed and heated at a temperature of from about 100° C. to about600° C., or from about 100° C. to about 650° C. in an inert atmosphere,thereby producing a thin film material photovoltaic absorber layer.

In some examples, a solar cell can be made by providing an electrodelayer on a polyethylene terephthalate substrate. A thin film materialphotovoltaic absorber layer can be coated onto the electrode layer asdescribed above. A window layer can be deposited onto the absorberlayer. A transparent conductive oxide layer can be deposited onto thewindow layer, thereby forming an embodiment of a solar cell.

Methods for making a photovoltaic absorber layer on a substrate includeproviding one or more polymeric precursor compounds, providing asubstrate, spraying the compounds onto the substrate, and heating thesubstrate at a temperature of from about 100° C. to about 600° C., or offrom about 100° C. to about 650° C. in an inert atmosphere, therebyproducing a photovoltaic absorber layer having a thickness of from 0.01to 100 micrometers. The spraying can be done in spray coating, spraydeposition, jet deposition, or spray pyrolysis. The substrate may beglass, metal, polymer, plastic, or silicon.

The photovoltaic absorber layer made by the methods of this disclosuremay have an empirical formulaCu_(x)(In_(1-y)Ga_(y))_(v)(S_(1-z)Se_(z))_(w), where x is from 0.8 to0.95, y is from 0 to 0.5, and z is from 0 to 1, v is from 0.95 to 1.05,and w is from 1.8 to 2.2. In some embodiments, w is from 2.0 to 2.2. Thephotovoltaic absorber layer made by the methods of this disclosure mayhave an empirical formula empirical formulaCu_(x)In_(y)(S_(1-z)Se_(z))_(w), where x is from 0.8 to 0.95, y is from0.95 to 1.05, z is from 0 to 1, and w is from 1.8 to 2.2. Methods formaking a photovoltaic absorber layer can include a step of sulfurizationor selenization.

In certain variations, methods for making a photovoltaic absorber layermay include heating the compounds to a temperature of from about 20° C.to about 400° C. while depositing, spraying, coating, or printing thecompounds onto the substrate.

Methods for making a photovoltaic absorber layer on a substrate includeproviding one or more polymeric precursor compounds, providing asubstrate, depositing the compounds onto the substrate, and heating thesubstrate at a temperature of from about 100° C. to about 650° C., orfrom about 100° C. to about 600° C., or from about 100° C. to about 400°C., or from about 100° C. to about 300° C. in an inert atmosphere,thereby producing a photovoltaic absorber layer having a thickness offrom 0.01 to 100 micrometers. The depositing can be done inelectrodepositing, electroplating, electroless plating, bath deposition,liquid deposition, solution deposition, layer-by-layer deposition, spincasting, or solution casting. The substrate may be glass, metal,polymer, plastic, or silicon.

Methods for making a photovoltaic absorber layer on a substrate includeproviding one or more polymeric precursor inks, providing a substrate,printing the inks onto the substrate, and heating the substrate at atemperature of from about 100° C. to about 600° C., or from about 100°C. to about 650° C. in an inert atmosphere, thereby producing aphotovoltaic absorber layer having a thickness of from 0.01 to 100micrometers. The printing can be done in screen printing, inkjetprinting, transfer printing, flexographic printing, or gravure printing.The substrate may be glass, metal, polymer, plastic, or silicon. Themethod may further include adding to the ink an additionalindium-containing compound, such as In(SeR)₃, wherein R is alkyl oraryl.

In general, an ink composition for depositing, spraying, or printing maycontain an additional indium-containing compound, or an additionalgallium-containing compound. Examples of additional indium-containingcompounds include In(SeR)₃, wherein R is alkyl or aryl. Examples ofadditional gallium-containing compounds include Ga(SeR)₃, wherein R isalkyl or aryl. For example, an ink may further contain In(Se^(n)Bu)₃ orGa(Se^(n)Bu)₃, or mixtures thereof. In some embodiments, an ink maycontain Na(ER), where E is S or Se and R is alkyl or aryl. In certainembodiments, an ink may contain NaIn(ER)₄, NaGa(ER)₄, LiIn(ER)₄,LiGa(ER)₄, KIn(ER)₄, or KGa(ER)₄, where E is S or Se and R is alkyl oraryl.

Electrical Power Generation and Transmission

This disclosure contemplates methods for producing and deliveringelectrical power. A photovoltaic device of this invention can be used,for example, to convert solar light to electricity which can be providedto a commercial power grid.

As used herein, the term “solar cell” refers to individual solar cell aswell as a solar cell array, which can combine a number of solar cells.

The solar cell devices of this disclosure can be manufactured in modularpanels.

The power systems of this disclosure can be made in large or smallscale, including power for a personal use, as well as on a megawattscale for a public use.

An important feature of the solar cell devices and power systems of thisdisclosure is that they can be manufactured and used with lowenvironmental impact.

A power system of this disclosure may utilize a solar cell on a movablemounting, which may be motorized to face the solar cell toward thelight. Alternatively, a solar cell may be mounted on a fixed object inan optimal orientation.

Solar cells can be attached in panels in which various groups of cellsare electrically connected in series and in parallel to provide suitablevoltage and current characteristics.

Solar cells can be installed on rooftops, as well as outdoor, sunlightedsurfaces of all kinds Solar cells can be combined with various kinds ofroofing materials such as roofing tiles or shingles.

A power system can include a solar cell array and a battery storagesystem. A power system may have a diode-containing circuit and avoltage-regulating circuit to prevent the battery storage system fromdraining through the solar cells or from being overcharged.

A power system can be used to provide power for lighting, electricvehicles, electric buses, electric airplanes, pumping water,desalinization of water, refrigeration, milling, manufacturing, andother uses.

Sources of Elements

Sources of silver include silver metal, Ag(I), silver nitrates, silverhalides, silver chlorides, silver acetates, silver alkoxides, andmixtures thereof.

Sources of alkali metal ions include alkali metals, alkali metal salts,alkali metal halides, alkali metal nitrates, selenides including Na₂Se,Li₂Se, and K₂Se, as well as organometallic compounds such asalkyllithium compounds.

Sources of copper include copper metal, Cu(I), Cu(II), copper halides,copper chlorides, copper acetates, copper alkoxides, copper alkyls,copper diketonates, copper 2,2,6,6,-tetramethyl-3,5,-heptanedionate,copper 2,4-pentanedionate, copper hexafluoroacetylacetonate, copperacetylacetonate, copper dimethylaminoethoxide, copper ketoesters, andmixtures thereof.

Sources of indium include indium metal, trialkylindium,trisdialkylamineindium, indium halides, indium chlorides, dimethylindiumchlorides, trimethylindium, indium acetylacetonates, indiumhexafluoropentanedionates, indium methoxyethoxides, indiummethyltrimethylacetylacetates, indium trifluoropentanedionates, andmixtures thereof.

Sources of gallium include gallium metal, trialkylgallium,trisdialkylamine gallium, gallium halides, gallium fluorides, galliumchlorides, gallium iodides, diethylgallium chlorides, gallium acetate,gallium 2,4-pentanedionate, gallium ethoxide, gallium2,2,6,6,-tetramethylheptanedionate, trisdimethylaminogallium, andmixtures thereof.

Sources of aluminum include aluminum metal, trialkylaluminum,trisdialkylamine aluminum, aluminum halides, aluminum fluorides,aluminum chlorides, aluminum iodides, diethylaluminum chlorides,aluminum acetate, aluminum 2,4-pentanedionate, aluminum ethoxide,aluminum 2,2,6,6,-tetramethylheptanedionate, trisdimethylaminoaluminum,and mixtures thereof.

Some sources of gallium and indium are described in International PatentPublication No. WO2008057119.

Additional Sulfurization or Selenization

In various processes of this disclosure, a composition or material mayoptionally be subjected to a step of sulfurization or selenization.

Selenization may be carried out with elemental selenium or Se vapor.Sulfurization may be carried out with elemental sulfur. Sulfurizationwith H₂S or selenization with H₂Se may be carried out by using pure H₂Sor H₂Se, respectively, or may be done by dilution in hydrogen or innitrogen.

A sulfurization or selenization step can be done at any temperature fromabout 200° C. to about 600° C., or from about 200° C. to about 650° C.,or at temperatures below 200° C. One or more steps of sulfurization andselenization may be performed concurrently, or sequentially.

Examples of sulfurizing agents include hydrogen sulfide, hydrogensulfide diluted with hydrogen, elemental sulfur, sulfur powder, carbondisulfide, alkyl polysulfides, dimethyl sulfide, dimethyl disulfide, andmixtures thereof.

Examples of selenizing agents include hydrogen selenide, hydrogenselenide diluted with hydrogen, elemental selenium, selenium powder,carbon diselenide, alkyl polyselenides, dimethyl selenide, dimethyldiselenide, and mixtures thereof.

A sulfurization or selenization step can also be done with co-depositionof another metal such as copper, indium, or gallium.

Chemical Definitions

As used herein, the term (X,Y) when referring to compounds or atomsindicates that either X or Y, or a combination thereof may be found inthe formula. For example, (S,Se) indicates that atoms of either sulfuror selenium, or any combination thereof may be found. Further, usingthis notation the amount of each atom can be specified. For example,when appearing in the chemical formula of a molecule, the notation(0.75In,0.25Ga) indicates that the atom specified by the symbols in theparentheses is indium in 75% of the compounds and gallium in theremaining 25% of the compounds, regardless of the identity any otheratoms in the compound. In the absence of a specified amount, the term(X,Y) refers to approximately equal amounts of X and Y.

The atoms S, Se, and Te of Group 16 are referred to as chalcogens.

As used herein, the letter “S” in CIGS, AIGS, CAIGS, CIGAS, AIGAS andCAIGAS refers to sulfur or selenium or both. The letter “C” in CIGS,CAIGS, CIGAS, and CAIGAS refers to copper. The letter “A” in AIGS,CAIGS, AIGAS and CAIGAS which appears before the letters I and G refersto silver. The letter “I” in CIGS, AIGS, CAIGS, CIGAS, AIGAS and CAIGASrefers to indium. The letter “G” in CIGS, AIGS, CAIGS, CIGAS, AIGAS andCAIGAS refers to gallium. The letter “A” in CIGAS, AIGAS and CAIGASwhich appears after the letters I and G refers to aluminum.

CAIGAS therefore could also be represented as Cu/Ag/In/Ga/Al/S/Se.

As used herein, the terms CIGS, AIGS, and CAIGS include the variationsC(I,G)S, A(I,G)S, and CA(I,G)S, respectively, and CIS, AIS, and CAIS,respectively, as well as CGS, AGS, and CAGS, respectively, unlessdescribed otherwise.

The terms CIGAS, AIGAS and CAIGAS include the variations C(I,G,A)S,A(I,G,A)S, and CA(I,G,A)S, respectively, and CIGS, AIGS, and CAIGS,respectively, as well as CGAS, AGAS, and CAGAS, respectively, unlessdescribed otherwise.

The term CAIGAS refers to variations in which either C or Silver iszero, for example, AIGAS and CIGAS, respectively, as well as variationsin which Aluminum is zero, for example, CAIGS, AIGS, and CIGS.

As used herein, the term CIGS includes the terms CIGSSe and CIGSe, andthese terms refer to compounds or materials containingcopper/indium/gallium/sulfur/selenium, which may contain sulfur orselenium or both. The term AIGS includes the terms AIGSSe and AIGSe, andthese terms refer to compounds or materials containingsilver/indium/gallium/sulfur/selenium, which may contain sulfur orselenium or both. The term CAIGS includes the terms CAIGSSe and CAIGSe,and these terms refer to compounds or materials containingcopper/silver/indium/gallium/sulfur/selenium, which may contain sulfuror selenium or both.

As used herein, the term “chalcogenide” refers to a compound containingone or more chalcogen atoms bonded to one or more metal atoms.

The term “alkyl” as used herein refers to a hydrocarbyl radical of asaturated aliphatic group, which can be a branched or unbranched,substituted or unsubstituted aliphatic group containing from 1 to 22carbon atoms. This definition applies to the alkyl portion of othergroups such as, for example, cycloalkyl, alkoxy, alkanoyl, aralkyl, andother groups defined below. The term “cycloalkyl” as used herein refersto a saturated, substituted or unsubstituted cyclic alkyl ringcontaining from 3 to 12 carbon atoms. As used herein, the term“C(1-5)alkyl” includes C(1)alkyl, C(2)alkyl, C(3)alkyl, C(4)alkyl, andC(5)alkyl. Likewise, the term “C(3-22)alkyl” includes C(1)alkyl,C(2)alkyl, C(3)alkyl, C(4)alkyl, C(5)alkyl, C(6)alkyl, C(7)alkyl,C(8)alkyl, C(9)alkyl, C(10)alkyl, C(11)alkyl, C(12)alkyl, C(13)alkyl,C(14)alkyl, C(15)alkyl, C(16)alkyl, C(17)alkyl, C(18)alkyl, C(19)alkyl,C(20)alkyl, C(21)alkyl, and C(22)alkyl.

The term “alkenyl” as used herein refers to an unsaturated, branched orunbranched, substituted or unsubstituted alkyl or cycloalkyl having 2 to22 carbon atoms and at least one carbon-carbon double bond. The term“alkynyl” as used herein refers to an unsaturated, branched orunbranched, substituted or unsubstituted alkyl or cycloalkyl having 2 to22 carbon atoms and at least one carbon-carbon triple bond.

The term “alkoxy” as used herein refers to an alkyl, cycloalkyl,alkenyl, or alkynyl group covalently bonded to an oxygen atom. The term“alkanoyl” as used herein refers to —C(═O)-alkyl, which mayalternatively be referred to as “acyl.” The term “alkanoyloxy” as usedherein refers to —O—C(═O)-alkyl groups. The term “alkylamino” as usedherein refers to the group —NRR′, where R and R′ are each eitherhydrogen or alkyl, and at least one of R and R′ is alkyl. Alkylaminoincludes groups such as piperidino wherein R and R′ form a ring. Theterm “alkylaminoalkyl” refers to -alkyl-NRR′.

The term “aryl” as used herein refers to any stable monocyclic,bicyclic, or polycyclic carbon ring system of from 4 to 12 atoms in eachring, wherein at least one ring is aromatic. Some examples of an arylinclude phenyl, naphthyl, tetrahydro-naphthyl, indanyl, and biphenyl.Where an aryl substituent is bicyclic and one ring is non-aromatic, itis understood that attachment is to the aromatic ring. An aryl may besubstituted or unsubstituted.

The term “heteroaryl” as used herein refers to any stable monocyclic,bicyclic, or polycyclic carbon ring system of from 4 to 12 atoms in eachring, wherein at least one ring is aromatic and contains from 1 to 4heteroatoms selected from oxygen, nitrogen and sulfur. Phosphorous andselenium may be a heteroatom. Some examples of a heteroaryl includeacridinyl, quinoxalinyl, pyrazolyl, indolyl, benzotriazolyl, furanyl,thienyl, benzothienyl, benzofuranyl, quinolinyl, isoquinolinyl,oxazolyl, isoxazolyl, pyrazinyl, pyridazinyl, pyridinyl, pyrimidinyl,pyrrolyl, and tetrahydroquinolinyl. A heteroaryl includes the N-oxidederivative of a nitrogen-containing heteroaryl.

The term “heterocycle” or “heterocyclyl” as used herein refers to anaromatic or nonaromatic ring system of from five to twenty-two atoms,wherein from 1 to 4 of the ring atoms are heteroatoms selected fromoxygen, nitrogen, and sulfur. Phosphorous and selenium may be aheteroatom. Thus, a heterocycle may be a heteroaryl or a dihydro ortetrathydro version thereof.

The term “aroyl” as used herein refers to an aryl radical derived froman aromatic carboxylic acid, such as a substituted benzoic acid. Theterm “aralkyl” as used herein refers to an aryl group bonded to an alkylgroup, for example, a benzyl group.

The term “carboxyl” as used herein represents a group of the formula—C(═O)OH or —C(═O)O⁻. The terms “carbonyl” and “acyl” as used hereinrefer to a group in which an oxygen atom is double-bonded to a carbonatom >C═O. The term “hydroxyl” as used herein refers to —OH or —O⁻. Theterm “nitrile” or “cyano” as used herein refers to —CN. The term“halogen” or “halo” refers to fluoro (—F), chloro (—Cl), bromo (—Br),and iodo (—I).

The term “substituted” as used herein refers to an atom having one ormore substitutions or substituents which can be the same or differentand may include a hydrogen substituent. Thus, the terms alkyl,cycloalkyl, alkenyl, alkynyl, alkoxy, alkanoyl, alkanoyloxy, alkylamino,alkylaminoalkyl, aryl, heteroaryl, heterocycle, aroyl, and aralkyl asused herein refer to groups which include substituted variations.Substituted variations include linear, branched, and cyclic variations,and groups having a substituent or substituents replacing one or morehydrogens attached to any carbon atom of the group. Substituents thatmay be attached to a carbon atom of the group include alkyl, cycloalkyl,alkenyl, alkynyl, alkoxy, alkanoyl, alkanoyloxy, alkylamino,alkylaminoalkyl, aryl, heteroaryl, heterocycle, aroyl, aralkyl, acyl,hydroxyl, cyano, halo, haloalkyl, amino, aminoacyl, alkylaminoacyl,acyloxy, aryloxy, aryloxyalkyl, mercapto, nitro, carbamyl, carbamoyl,and heterocycle. For example, the term ethyl includes without limitation—CH₂CH₃, —CHFCH₃, —CF₂CH₃, —CHFCH₂F, —CHFCHF₂, —CHFCF₃, —CF₂CH₂F,—CF₂CHF₂, —CF₂CF₃, and other variations as described above. In general,a substituent may itself be further substituted with any atom or groupof atoms.

Some examples of a substituent for a substituted alkyl include halogen,hydroxyl, carbonyl, carboxyl, ester, aldehyde, carboxylate, formyl,ketone, thiocarbonyl, thioester, thioacetate, thioformate,selenocarbonyl, selenoester, selenoacetate, selenoformate, alkoxyl,phosphoryl, phosphonate, phosphinate, amino, amido, amidine, imino,cyano, nitro, azido, carbamato, sulfhydryl, alkylthio, sulfate,sulfonate, sulfamoyl, sulfonamido, sulfonyl, silyl, heterocyclyl, aryl,aralkyl, aromatic, and heteroaryl.

It will be understood that “substitution” or “substituted with” refersto such substitution that is in accordance with permitted valence of thesubstituted atom and the substituent. As used herein, the term“substituted” includes all permissible substituents.

In general, a compound may contain one or more chiral centers. Compoundscontaining one or more chiral centers may include those described as an“isomer,” a “stereoisomer,” a “diastereomer,” an “enantiomer,” an“optical isomer,” or as a “racemic mixture.” Conventions forstereochemical nomenclature, for example the stereoisomer naming rulesof Cahn, Ingold and Prelog, as well as methods for the determination ofstereochemistry and the separation of stereoisomers are known in theart. See, for example, Michael B. Smith and Jerry March, March'sAdvanced Organic Chemistry, 5th edition, 2001. The compounds andstructures of this disclosure are meant to encompass all possibleisomers, stereoisomers, diastereomers, enantiomers, and/or opticalisomers that would be understood to exist for the specified compound orstructure, including any mixture, racemic or otherwise, thereof.

This invention encompasses any and all tautomeric, solvated orunsolvated, hydrated or unhydrated forms, as well as any atom isotopeforms of the compounds and compositions disclosed herein.

This invention encompasses any and all crystalline polymorphs ordifferent crystalline forms of the compounds and compositions disclosedherein.

Additional Embodiments

All publications, references, patents, patent publications and patentapplications cited herein are each hereby specifically incorporated byreference in their entirety for all purposes.

While this invention has been described in relation to certainembodiments, aspects, or variations, and many details have been setforth for purposes of illustration, it will be apparent to those skilledin the art that this invention includes additional embodiments, aspects,or variations, and that some of the details described herein may bevaried considerably without departing from this invention. Thisinvention includes such additional embodiments, aspects, and variations,and any modifications and equivalents thereof. In particular, thisinvention includes any combination of the features, terms, or elementsof the various illustrative components and examples.

The use herein of the terms “a,” “an,” “the” and similar terms indescribing the invention, and in the claims, are to be construed toinclude both the singular and the plural.

The terms “comprising,” “having,” “include,” “including” and“containing” are to be construed as open-ended terms which mean, forexample, “including, but not limited to.” Thus, terms such as“comprising,” “having,” “include,” “including” and “containing” are tobe construed as being inclusive, not exclusive.

Recitation of a range of values herein refers individually to each andany separate value falling within the range as if it were individuallyrecited herein, whether or not some of the values within the range areexpressly recited. For example, the range “4 to 12” includes withoutlimitation any whole, integer, fractional, or rational value greaterthan or equal to 4 and less than or equal to 12, as would be understoodby those skilled in the art. Specific values employed herein will beunderstood as exemplary and not to limit the scope of the invention.

Recitation of a range of a number of atoms herein refers individually toeach and any separate value falling within the range as if it wereindividually recited herein, whether or not some of the values withinthe range are expressly recited. For example, the term “C1-8” includeswithout limitation the species C1, C2, C3, C4, C5, C6, C7, and C8.

Definitions of technical terms provided herein should be construed toinclude without recitation those meanings associated with these termsknown to those skilled in the art, and are not intended to limit thescope of the invention. Definitions of technical terms provided hereinshall be construed to dominate over alternative definitions in the artor definitions which become incorporated herein by reference to theextent that the alternative definitions conflict with the definitionprovided herein.

The examples given herein, and the exemplary language used herein aresolely for the purpose of illustration, and are not intended to limitthe scope of the invention. All examples and lists of examples areunderstood to be non-limiting.

When a list of examples is given, such as a list of compounds, moleculesor compositions suitable for this invention, it will be apparent tothose skilled in the art that mixtures of the listed compounds,molecules or compositions may also be suitable.

EXAMPLES

Thermogravimetric analysis (TGA) was performed using a Q50Thermogravimetric Analyzer (TA Instruments, New Castle, Del.). NMR datawere recorded using a Varian 400 MHz spectrometer.

Example 1 Controlling the Stoichiometry of Polymeric Precursors

FIG. 8 shows results of methods for preparing polymeric precursorembodiments (MPP) of this invention having predetermined stoichiometrywhich are useful for preparing CIS and CIGS materials of the samepredetermined stoichiometry. The x-axis of FIG. 8 refers to the weightpercent of a particular atom, either Cu, In or Ga, in the monomercompounds used to prepare the polymeric precursor. The y-axis refers tothe weight percent of a particular atom in the synthesized polymericprecursor compounds. Atom concentrations were determined by the use ofICP. The linear correlation observed in FIG. 8 for several differentpolymeric precursor compounds showed that the stoichiometries of thepolymeric precursors were precisely controlled by the quantities andcompositions of the monomers used to make the polymeric precursors. Thelinear correlation observed in FIG. 8 also showed that methods of thisdisclosure can be used to make precursor compounds having a range ofarbitrary stoichiometries.

Example 2

FIG. 9 shows results of methods for preparing polymeric precursorembodiments (MPP) of this invention having predetermined stoichiometrywhich are useful for preparing AIS, AIGS, CAIS, and CAIGS materials ofthe same predetermined stoichiometry. The x-axis of FIG. 9 refers to theweight percent of atoms of a particular kind, either In or Ga, in themonomer compounds used to prepare the polymeric precursor. The y-axisrefers to the weight percent of atoms of a particular kind in thesynthesized polymeric precursor compounds. Atom concentrations weredetermined by the use of ICP. The linear correlation observed in FIG. 9for several different polymeric precursor compounds showed that thestoichiometries of the polymeric precursors were precisely controlled bythe quantities and compositions of the monomers used to make thepolymeric precursors. The linear correlation observed in FIG. 9 alsoshowed that methods of this disclosure can be used to make precursorcompounds having a range of arbitrary stoichiometries.

Example 3 Controlling the Stoichiometry of Bulk, Crystalline CIGSMaterials Using Polymeric Precursors

FIG. 10 shows results of methods for controlling the stoichiometry ofthe composition of a bulk, crystalline CIGS material. In these results,the ratio of indium to gallium was controlled. FIG. 10 shows an analysisby X-ray diffraction of the structure of the crystalline phase of bulkCIGS materials made with various polymeric precursors. The ratio ofindium to gallium in the crystals of CIGS materials was detected by therelative positions of the 2-theta-(112) peaks in the X-ray diffractionpatterns. As shown in FIG. 10, a linear correlation was found betweenthe percent indium in the bulk CIGS materials and the positions of the2-theta-(112) peaks over a range of percent indium from about 30% toabout 90%, corresponding to a ratio of indium to gallium in the bulkCIGS materials of 30:70 to 90:10, respectively. The CIGS materials wereeach made from a polymeric precursor having a percent indiumcorresponding to the value on the x-axis. Thus, the results showed thatthe ratio of indium to gallium of a CIGS material was preciselycontrolled by the structure of the polymeric precursor used for itspreparation.

Example 4 Controlling the Stoichiometry of Bulk, Crystalline AIGSMaterials Using Polymeric Precursors

FIG. 11 shows results of methods for controlling the stoichiometry ofthe composition of a bulk, crystalline AIGS material. In these results,the ratio of indium to gallium was controlled. FIG. 11 shows an analysisby X-ray diffraction of the structure of the crystalline phase of bulkAIGS materials made with various polymeric precursors. The ratio ofindium to gallium in the crystals of AIGS materials was detected by therelative positions of the 2-theta-(112) peaks of the X-ray diffractionpatterns. As shown in FIG. 11, a linear correlation was found betweenthe percent indium in the bulk AIGS materials and the positions of the2-theta-(112) peaks over a range of percent indium from 0% to 100%,corresponding to a ratio of indium to gallium in the bulk AIGS materialsof 0:100 to 100:0, respectively. The AIGS materials were each made froma polymeric precursor having a percent indium corresponding to the valueon the x-axis. Thus, the results showed that the ratio of indium togallium of an AIGS material was precisely controlled by the structure ofthe polymeric precursor used for its preparation.

Example 5 Controlling the Stoichiometry of Thin Film CIGS MaterialsUsing Polymeric Precursors

FIG. 12 shows results of methods for controlling the stoichiometry ofthe atoms of Group 13 in CIGS thin film layers. The CIGS thin films weremade by spin coating a polymeric precursor embodiment (MPP) of thisinvention onto a substrate, and converting the coated polymericprecursor to a CIGS composition. The MPP polymeric precursor had apredetermined stoichiometry of Group 13 atoms, and was used to make aCIGS thin film having the same predetermined stoichiometry. The x-axisof FIG. 12 refers to the fraction of the Group 13 atoms in the polymericprecursor that were indium atoms, which represents the predetermined ortargeted indium to gallium stoichiometry. The y-axis of FIG. 12 refersto the fraction of the Group 13 atoms in the CIGS thin film that wereindium atoms, which represents the measured indium to galliumstoichiometry as determined by the use of EDX. The line of unit sloperepresents a match between the predetermined or targeted indium togallium stoichiometry and the actual stoichiometry found in the CIGSthin film.

The CIGS thin films had a thickness of about 500-700 nm and were made byspin coating a CIGS polymeric precursor onto a Mo-coated glasssubstrate.

For spin coating, an ink was made in an inert atmosphere glove box bydissolving a polymeric precursor in xylene solvent to about 20%precursor content (w/w). About 0.3 mL of the ink was passed through asyringe filter (PTFE, 0.2 micron) onto a Mo-coated glass substrate,which was sufficient to cover the entire substrate surface. Thesubstrate was then spun at 1200 rpm for about 60 s. After a brief dryingperiod at room temperature, typically 1-2 minutes, the coated substratewas heated in a furnace for conversion of the polymeric molecularprecursor film to a semiconductor thin film material.

The data points for the thin CIGS films in FIG. 12 fall close to theideal line. Thus, a straight line correlation was observed between thestoichiometric ratio of indium to gallium in a number of differentpolymeric precursor compounds and the stoichiometric ratio of indium togallium in the corresponding thin CIGS film. These results show that theratio of indium to gallium in a thin CIGS film can be preciselycontrolled by the predetermined stoichiometric ratio of indium togallium in the polymeric precursor used to make the CIGS material. Thecorrelation observed in FIG. 12 also shows that the methods of thisinvention can be used to make CIGS thin films of any arbitrary desiredstoichiometry with respect to the atoms of Group 13.

Example 6

FIG. 13 shows results of methods for controlling the stoichiometry ofGroup 13 atoms in thin film CIGS materials. In these results, the ratioof indium to gallium was controlled. FIG. 13 shows an analysis by X-raydiffraction of the structure of the crystalline phase of CIGS thin filmmaterials made with various polymeric precursors.

The CIGS thin films were made by spin coating and rod coating. Thethickness of the thin films was about 300 nm for rod coating and in therange of about 500-700 nm for spin coating. The thin films were made bycoating an ink of a polymeric precursor onto a sputtered-molybdenumlayer on a glass substrate, and converting the coating to a thin filmmaterial in a furnace.

The x-axis of FIG. 13 refers to the fraction of the Group 13 atoms inthe thin film that were indium atoms, which represents the indium togallium stoichiometry measured by EDX. The y-axis of FIG. 13 refers tothe position of the 2-theta-(112) peak in the X-ray diffraction patternof the thin film CIGS material on the substrate after conversion. TheCIGS thin films were each made from a polymeric precursor having apercent indium corresponding to the same value on the x-axis, wherepercent indium is 100*In/(In+Ga).

The results in FIG. 13 showed that the ratios of indium to gallium inthe CIGS thin films were detected by the relative positions of the2-theta-(112) peaks in the X-ray diffraction patterns of the thin films.The straight line in FIG. 13 is a best fit to the data points and showsa correlation between the measured indium to gallium stoichiometry andthe position of the 2-theta-(112) peak in the X-ray diffraction pattern.

Thus, a linear correlation was found between the measured indium togallium stoichiometry of the thin film and the position of the2-theta-(112) peak over a range of percent indium from 0% to 100%. Thus,the results showed that the stoichiometry of the atoms of Group 13 of athin film CIGS material can be precisely controlled by the structure ofthe polymeric precursor used for its preparation. Further, thecorrelation observed in FIG. 13 shows that the methods of this inventioncan be used to make CIGS thin films of any arbitrary desiredstoichiometry with respect to the atoms of Group 13.

Example 7 Thin Film CIS/CIGS/CGS Materials Having PredeterminedStoichiometry Made from Polymeric Precursors

Examples of thin film CIGS, CIS and CGS materials made from polymericprecursors having predetermined stoichiometry are shown in Table 2. Theexamples in Table 2 were made by coating an ink containing 15-20% (w/w)of the specified polymeric precursor in solvent onto a molybdenum-glasssubstrate, drying the coating, and converting and annealing to achieve athin film.

TABLE 2 Thin film CIGS, CIS and CGS materials made from polymericprecursors having predetermined stoichiometry Drying Conversion Method(layers) thickness (T° C.) (T° C.) Annealing Ink %; Polymeric Precursor(min) (h) (T° C.) (h) Solvent spin coat (10) 700 nm 110 260 400 C., 1 h;p-xylene 20% [Cu_(1.0)In_(1.0)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat(10) 700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(0.8)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.8)]_(n) 15 1 650 C. 1 h spin coat(10) 700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 1 650 C. 1 h spin coat(10) 700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.85)]_(n) 15 1 650 C. 1 h spincoat (10) 700 nm 110 260 400 C., 1 h; 650 C. p-xylene 20%[Cu_(1.0)In_(0.8)Ga_(0.2)(Se^(s)Bu)₄]_(n) 15 1 1 h spin coat (10) 700 nm110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.6)Ga_(0.4)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)Ga_(1.0)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10) 700 nm110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.1)Ga_(0.9)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h spin coat (10)700 nm 110 260 400 C., 1 h; p-xylene 20%[Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(s)Bu)₄]_(n) 15 1 650 C. 1 h rod coat (5)300 nm r.t. 200 C., 1 h; 400 C., 1 h THF 20%[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n) 1-2 260 C., 15 min spin coat(10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)In_(1.0)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110 260 400C., 1 h p-xylene 20% [Cu_(0.8)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.8)]_(n) 15 1spin coat (10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 1 spin coat (10) 700nm 110 260 400 C., 1 h p-xylene 20%[Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.85)]_(n) 15 1 spin coat (10) 700nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)In_(0.8)Ga_(0.2)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110260 400 C., 1 h p-xylene 20% [Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(s)Bu)₄]_(n)15 1 spin coat (10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)In_(0.6)Ga_(0.4)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110260 400 C., 1 h p-xylene 20% [Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n)15 1 spin coat (10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)Ga_(1.0)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110 260 400C., 1 h p-xylene 20% [Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)₄]_(n) 15 1 spincoat (10) 700 nm 110 260 400 C., 1 h p-xylene 20%[Cu_(1.0)In_(0.1)Ga_(0.9)(Se^(s)Bu)₄]_(n) 15 1 spin coat (10) 700 nm 110260 400 C., 1 h p-xylene 20% [Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(s)Bu)₄]_(n)15 1 spin coat (15) 1200 nm r.t. 300 C., 550 C., 1 hr p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min spincoat (10) 800 nm r.t. 300 C., 550 C., 1 hr p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min rodcoat (10) 700 nm r.t. 300 C., 550 C., 1 h THF 20%[Cu_(1.0)In_(1.0)(Se^(n)Hex)₄]_(n) 1-2 flash rod coat (10) 700 nm r.t.300 C., 550 C., 1 h THF 20% [Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(n)Hex)₄]_(n)1-2 flash rod coat (10) 700 nm r.t. 300 C., 550 C., 1 h THF 20%[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(n)Hex)₄]_(n) 1-2 flash rod coat (10) 700nm r.t. 300 C., 550 C., 1 h THF 20%[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(n)Hex)₄]_(n) 1-2 flash spin coat (9) 500nm r.t. 300 C., 500 C. 2 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min every3rd coat spin coat (11) 700 nm r.t. 300 C., 500 C. 2 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min every3rd coat spin coat (12) 700 nm r.t. 300 C., 500 C. 2 h 3/6/9, p-xylene20% [Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min 5503 h 12th coat spin coat (12) 700 nm r.t. 300 C., 500 C. 2 h 3/6/9,p-xylene 20% [Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash30 min 550 3 h 12th coat, 600 8 h spin coat (5) 300 nm r.t. 300 C., 550C., 1 h p-xylene 20% [Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2flash 30 min spin coat (10) 600 nm r.t. 300 C., 550 C., 1 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min spincoat (15) 1000 nm r.t. 300 C., 550 C., 1 h 10th, p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 30 min 550 C.1 h 15th spin coat (15) 1100 nm r.t. 300 C., none p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) 1-2 flash 30 minspin coat (15) 1100 nm r.t. 300 C., 400 C., 1 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) 1-2 flash 30 minspin coat (15) 1000 nm r.t. 300 C., 550 C., 1 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) 1-2 flash 30 minspin coat (10) 700 nm r.t. 300 C., none decane 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) 1-2 flash 30 minspin coat (15) 950 nm r.t. 300 C., 400 C., 1 h decane 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) 1-2 flash 30 minspin coat (15) 950 nm r.t. 300 C., 550 C., 1 h decane 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) 1-2 flash 30 min rodcoat (8) 500 nm r.t. 300 C., 550 C., 1 h THF add. NaIn(Se-secBu)4 1-2flash 10 min 15% [Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) spincoat (10) 700 nm 110 260 C., 1 h 650 C., 4 h p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 spin coat (10) 700 nm110 260 C., 1 h 400 C., 1 h, 650 C. p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 2 h, 650 C., 4 h spincoat (10) 700 nm 110 260 C., 1 h 650 C., 4 h, 650 C., p-xylene 20%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.9)]_(n) 15 4 h knife coat (10)1000 nm r.t. 300 C., 550 C., 1 h c-C₆H₁₂ 27%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.9)]_(n) 1-2 flash 10 min C₇H₁₆knife coat (10) 1000 nm r.t. 300 C., 550 C., 1 h 5^(th) c-C₆H₁₂ 25%[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.9)]_(n) 1-2 flash 10min 550 C., 1 h 10^(th) C₇H₁₆

In Table 3 are shown SIMS data for thin film CIGS materials made frompolymeric precursors having predetermined stoichiometry. The results inTable 3 indicate that embodiments of this invention provide polymericprecursor compounds that can be used to prepare CIGS with any desiredstoichiometry of the ratios of atoms of Group 13.

TABLE 3 SIMS stoichiometry data for thin film CIGS materials made frompolymeric precursors having predetermined stoichiometry Average AverageIn/(In + Ga) Ga/(In + Ga) spin coat (15) 1100 nm SIMS 0.69 0.31 20%(In/Ga) [Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) spin coat(15) 1000 nm SIMS 0.68 0.32 20% (In/Ga)[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) spin coat (10) 700nm SIMS 0.68 0.32 20% (In/Ga)[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) spin coat (15) 950nm SIMS 0.68 0.32 20% (In/Ga)[Cu_(0.9)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)

Example 8 Preparation of Bulk CIGS Materials

A bulk CIGS material was prepared from a polymeric precursor as follows.A sample of the polymeric precursor{(Cu)(Se^(t)Bu)(Se^(n)Bu)(0.75In,0.25Ga)(Se^(n)Bu)₂} (40-60 mg) wasinitially heated from 20° C. to 260° C. over a period of about 1.5 h inan inert atmosphere (nitrogen). The sample was allowed to cool to roomtemperature before a second heating sequence was performed in which thesample was heated at 10° C./min from 20° C. to 250° C., followed byheating at 2° C./min to 400° C. The resulting CIGS material was cooledto 20° C. over a period of about 1 h.

Example 9

A bulk CIGS material was prepared from a polymeric precursor as follows.A sample of the polymeric precursor{(0.85Cu)(Se^(t)Bu)(Se^(n)Bu)(0.7In,0.3Ga)(Se^(n)Bu)₂} (40-60 mg) wasinitially heated from 20° C. to 260° C. over a period of about 1.5 h inan inert atmosphere (nitrogen). The sample was allowed to cool to roomtemperature before a second heating sequence was performed in which thesample was heated at 10° C./min from 20° C. to 250° C., followed byheating at 2° C./min to 400° C. The resulting CIGS material was cooledto 20° C. over a period of about 1 h.

The X-ray diffraction pattern of this material indicated the presence ofa single crystalline CIGS phase, namely a tetragonal chalcopyrite phase.

Elemental analysis (EDS): Cu_(0.83)In_(0.68)Ga_(0.32)Se_(2.2).

Elemental analysis (ICP): Cu_(0.91)In_(0.67)Ga_(0.33)Se_(1.8).

Example 10

A bulk CIGS material was prepared from a polymeric precursor as follows.A sample of the polymeric precursor{(^(n)BuSe)₂In_(0.3)Ga_(0.7)(Se^(n)Bu)(Se^(t)Bu)Cu} (40-60 mg) wasinitially heated from 20° C. to 260° C. over a period of about 1.5 h inan inert atmosphere (nitrogen). The sample was allowed to cool to roomtemperature before a second heating sequence was performed in which thesample was heated at 10° C./min from 20° C. to 250° C., followed byheating at 2° C./min to 400° C. The resulting CIGS material was cooledto 20° C. over a period of about 1 h.

Example 11

A bulk CIGS material was prepared from a polymeric precursor as follows.A sample of the polymeric precursor{(^(n)BuSe)₂In_(0.5)Ga_(0.5)(Se^(n)Bu)(Se^(t)Bu)Cu} (40-60 mg) wasinitially heated from 20° C. to 260° C. over a period of about 1.5 h inan inert atmosphere (nitrogen). The sample was allowed to cool to roomtemperature before a second heating sequence was performed in which thesample was heated at 10° C./min from 20° C. to 250° C., followed byheating at 2° C./min to 400° C. The resulting CIGS material was cooledto 20° C. over a period of about 1 h.

Example 12

A bulk CIGS material was prepared from a polymeric precursor as follows.A sample of the polymeric precursor{(^(n)BuSe)₂In_(0.7)Ga_(0.3)(Se^(n)Bu)(Se^(t)Bu)Cu} (40-60 mg) wasinitially heated from 20° C. to 260° C. over a period of about 1.5 h inan inert atmosphere (nitrogen). The sample was allowed to cool to roomtemperature before a second heating sequence was performed in which thesample was heated at 10° C./min from 20° C. to 250° C., followed byheating at 2° C./min to 400° C. The resulting CIGS material was cooledto 20° C. over a period of about 1 h.

Example 13

A bulk CIGS material was prepared from a polymeric precursor as follows.A sample of the polymeric precursor{(^(n)BuSe)₂In_(0.9)Ga_(0.1)(Se^(n)Bu)(Se^(t)Bu)Cu} (40-60 mg) wasinitially heated from 20° C. to 260° C. over a period of about 1.5 h inan inert atmosphere (nitrogen). The sample was allowed to cool to roomtemperature before a second heating sequence was performed in which thesample was heated at 10° C./min from 20° C. to 250° C., followed byheating at 2° C./min to 400° C. The resulting CIGS material was cooledto 20° C. over a period of about 1 h.

Example 14 Preparation of Bulk AIS Materials

A bulk AIS material having the formula AgInSe₂ was prepared by heatingthe polymeric precursor {Ag(Se^(s)Bu)₄In} at 10° C. per minute to afinal temperature of 500° C. and holding the temperature at 500° C. for30 minutes. The X-ray diffraction pattern of this material indicated thepresence of a crystalline AIS phase.

Example 15

A bulk AIS material having the formula Ag_(0.9)InSe₂ was prepared byheating the polymeric precursor {Ag_(0.9)(Se^(s)Bu)_(3.9)In} at 10° C.per minute to a final temperature of 500° C. and holding the temperatureat 500° C. for 30 minutes. The X-ray diffraction pattern of thismaterial indicated the presence of a crystalline AIS phase.

Example 16 Preparation of Bulk CAIS Materials

A bulk CAIS material having the formula Cu_(0.05)Ag_(0.95)InSe₂ wasprepared by heating the polymeric precursor {Cu_(0.05)Ag_(0.95(Se)^(s)Bu)₄In} at 10° C. per minute to a final temperature of 500° C. andholding the temperature at 500° C. for 30 minutes. The X-ray diffractionpattern of this material indicated the presence of a crystalline CAISphase.

Example 17

A bulk CAIS material having the formula Cu_(0.1)Ag_(0.9)InSe₂ wasprepared by heating the polymeric precursor{Cu_(0.1)Ag_(0.9)(Se^(s)Bu)₄In} at 10° C. per minute to a finaltemperature of 500° C. and holding the temperature at 500° C. for 30minutes. The X-ray diffraction pattern of this material indicated thepresence of a crystalline CAIS phase.

Example 18 Spin Casting Deposition of Polymeric Precursor InkCompositions

A polymeric precursor ink was prepared by mixingCu_(0.85)Ag_(0.05)(Se^(s)Bu)_(3.9)In_(0.7)Ga_(0.3) with xylene (15%polymer content, by weight) in an inert atmosphere glove box. An aliquot(0.3 mL) of the ink solution was filtered through a 0.2 μm PTFE syringefilter and deposited onto a piece of 1 inch by 1 inch Mo-coated glasssubstrate in a raster fashion. The substrate was spun at 1200 rpm for 1minute using a G3P-8 Spin Coater (Specialty Coating Systems) in an inertatmosphere glove box, allowed to sit for about 2 minutes, and placed ina pre-heated (300° C.) furnace for 30 minutes for conversion of thepolymer to a CAIGS material. This deposition process(filter/deposit/convert) was repeated 7 and 14 times, with the finaldeposition and conversion followed by annealing in a furnace at 550° C.for 1 hour. The CAIGS film resulting from 7 depositions had a thicknessof about 400 nm. The CAIGS film resulting from 14 depositions had athickness of about 850 nm.

Example 19

A polymeric precursor ink was made by mixingCu_(0.8)Ag_(0.05)(Se^(s)Bu)_(3.85)In_(0.7)Ga_(0.3) with xylene (15%polymer content, by weight) in an inert atmosphere glove box. An aliquot(0.3 mL) of the ink solution was filtered through a 0.2 μm PTFE syringefilter and deposited onto a piece of 1 inch by 1 inch Mo-coated glasssubstrate in a raster fashion. The substrate was spun at 1200 rpm for 1minute using a G3P-8 Spin Coater (Specialty Coating Systems) in an inertatmosphere glove box, allowed to sit for about 2 minutes, and placed ina pre-heated (300° C.) furnace for 30 minutes for conversion of thepolymer to a CAIGS material. This deposition process(filter/deposit/convert) was repeated 7 times, with the final depositionand conversion followed by annealing in a furnace at 550° C. for 1 hour.The CAIGS film resulting from this deposition had a thickness of about400 nm.

Example 20 Spin Casting Deposition of Polymeric Precursor InkCompositions

An ink made by mixing AgIn(Se^(n)Hex)₄ with xylene (20% polymer content,by weight) was prepared in an inert atmosphere glove box. An aliquot(0.3 mL) of the ink solution was filtered through a 0.2 μm PTFE syringefilter and deposited onto a piece of 1 inch by 1 inch Mo-coated glasssubstrate in a raster fashion. The substrate was spun at 1200 rpm for 1minute using a G3P-8 Spin Coater (Specialty Coating Systems) in an inertatmosphere glove box, allowed to sit for about 2 minutes, and placed ina pre-heated (300° C.) furnace for 30 minutes for conversion of thepolymeric precursor to an AIS material. This deposition process(filter/deposit/convert) was repeated 8 times, with the finaldeposition/conversion followed by annealing in a furnace at 550° C. for1 hour. The AIS film had a thickness of about 500 nm.

Example 21 Preparation of Monomer Compounds

A monomer compound represented by the formula Ga(Se^(n)Bu)₃ wassynthesized using the following procedure.

To a 500-mL round bottom Schlenk flask in an inert atmosphere glove boxwas added NaSe^(n)Bu (28 g, 176 mmol) and THF (200 mL). The flask wasthen transferred to a Schlenk line and a solution of GaCl₃ (10.3 g, 59mmol) in 20 mL of benzene was then added. The reaction mixture wasstirred for 12 h and the volatiles were removed under reduced pressure.The residue was extracted with toluene and filtered. The volatiles fromthe filtrate were then removed under reduced pressure leaving acolorless oil (23 g, 48 mmol, 83% yield).

NMR: (1H; C6D6): 0.85 (t, J_(HH)=7.2 Hz, 9H, CH₃); 1.40 (m, 6H, —CH₂—);1.77 (m, 6H, —CH₂—); 3.03 (br s, 6H, SeCH₂—).

Example 22

A monomer compound represented by the formula In(Se^(n)Bu)₃ wassynthesized using the following procedure.

To a 500-mL round bottom Schlenk flask in an inert atmosphere glove boxwas added InCl₃ (6.95 g, 31 mmol), NaSe^(n)Bu (15 g, 94 mmol), and THF(200 mL). The reaction mixture was transferred to a Schlenk line andstirred for 12 h. The volatiles were subsequently removed under reducedpressure. The remaining solid residue was dissolved in hot toluene andfiltered. The volatiles from the filtrate were removed under reducedpressure and the resulting solid was washed with pentane. The finalcolorless solid was dried under reduced pressure and isolated (15 g, 29mmol, 92% yield).

NMR: (1H; C6D6): 0.913 (t, J_(HH)=7.2 Hz, 9H, CH₃); 1.43 (m, 6H, —CH₂—);1.72 (m, 6H, —CH₂—); 2.90 (t, J_(HH)=7.2 Hz, 6H, SeCH₂—).

Example 23

A range of polymeric molecular precursors shown in Table 4 weresynthesized in an inert atmosphere according to the following generalprocedure. A Schlenk tube was charged in an inert atmosphere gloveboxwith M^(B)(ER)₃ and Cu(ER). A solvent, typically toluene or benzene, wasthen added. The Schlenk tube was transferred to a Schlenk line and thereaction mixture was stirred at 25° C. for 1 h. In some cases, thereaction mixture was stirred at about 80° C. for up to 12 h. The solventwas removed under reduced pressure and the product was extracted withpentane. The pentane extract was filtered and the solvent was removedunder reduced pressure to afford a yellow to yellow-orange product. Theproducts ranged from being an oil, to being a semi-solid, to being asolid. Yields of 90% or greater were typical.

TABLE 4 Examples of polymeric molecular precursors TGA PolymericMolecular Precursor Material Target Yield % Target %[Cu_(1.0)In_(1.0)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(1.0)Se₂ 46.6 46.5[Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(0.9)Ga_(0.1)Se₂46.3 46.2 [Cu_(1.0)In_(0.8)Ga_(0.2)(Se^(s)Bu)₄]_(n)Cu_(1.0)In_(0.8)Ga_(0.2)Se₂ 45.2 45.9[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(0.7)Ga_(0.3)Se₂46.0 45.5 [Cu_(1.0)In_(0.6)Ga_(0.4)(Se^(s)Bu)₄]_(n)Cu_(1.0)In_(0.6)Ga_(0.4)Se₂ 49.0 45.2[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(0.5)Ga_(0.5)Se₂45.8 44.8 [Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(s)Bu)₄]_(n)Cu_(1.0)In_(0.3)Ga_(0.7)Se₂ 48.9 44.1[Cu_(1.0)In_(0.1)Ga_(0.9)(Se^(s)Bu)₄]_(n) Cu_(1.0)In_(0.1)Ga_(0.9)Se₂49.0 43.4 [Cu_(1.0)Ga_(1.0)(Se^(s)Bu)₄]_(n) Cu_(1.0)Ga_(1.0)Se₂ 44.043.0 [Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.85)]_(n)Cu_(0.85)In_(0.7)Ga_(0.3)Se₂ 46.7 46.1[Cu_(0.90)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.90)]_(n)Cu_(0.90)In_(0.7)Ga_(0.3)Se₂ 47.8 45.9[Cu_(0.95)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.95)]_(n)Cu_(0.95)In_(0.7)Ga_(0.3)Se₂ 47.4 45.7[Cu_(1.0)In_(1.0)(Se^(n)Hex)₄]_(n) Cu_(1.0)In_(1.0)Se₂ 38.3 40.3[Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(n)Hex)₄]_(n) Cu_(1.0)In_(0.9)Ga_(0.1)Se₂42.8 40.0 [Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(n)Hex)₄]_(n)Cu_(1.0)In_(0.7)Ga_(0.3)Se₂ 39.5 39.3[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(n)Hex)₄]_(n) Cu_(1.0)In_(0.5)Ga_(0.5)Se₂37.9 38.6 [Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(n)Hex)₄]_(n)Cu_(1.0)In_(0.3)Ga_(0.7)Se₂ 38.0 37.9 [Cu_(1.0)Ga_(1.0)(Se^(n)Hex)₄]_(n)Cu_(1.0)Ga_(1.0)Se₂ 38.3 36.9[Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.85)]_(n)Cu_(0.85)In_(0.7)Ga_(0.3)Se₂ 40.7 39.8[Cu_(0.90)In_(0.7)Ga_(0.3)(Se^(n)Hex)_(3.90)]_(n)Cu_(0.90)In_(0.7)Ga_(0.3)Se₂ 40.3 39.6 [Cu_(1.0)In_(1.0)(Se^(n)Bu)₄]_(n)Cu_(1.0)In_(1.0)Se₂ 47.2 46.5 [Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(n)Bu)₄]_(n)Cu_(1.0)In_(0.7)Ga_(0.3)Se₂ 43.8 45.5 [Cu_(1.0)Ga_(1.0)(Se^(n)Bu)₄]_(n)Cu_(1.0)Ga_(1.0)Se₂ 43.8 43.0[Cu_(1.0)In_(1.0)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) Cu_(1.0)In_(1.0)Se₂ 48.846.6 [Cu_(1.0)In_(0.9)Ga_(0.1)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.9)Ga_(0.1)Se₂ 49.3 46.2[Cu_(1.0)In_(0.75)Ga_(0.25)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.75)Ga_(0.25)Se₂ 47.3 45.7[Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.7)Ga_(0.3)Se₂ 49.3 45.5[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.5)Ga_(0.5)Se₂ 46.9 44.8[Cu_(1.0)In_(0.3)Ga_(0.7)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.3)Ga_(0.7)Se₂ 48.5 44.1[Cu_(1.0)In_(0.1)Ga_(0.9)(Se^(n)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.1)Ga_(0.9)Se₂ 44.2 43.4[Cu_(1.0)Ga_(1.0)(Se^(n)Bu)₃(Se^(t)Bu)]_(n) Cu_(1.0)Ga_(1.0)Se₂ 45.043.0 [Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.85)]_(n)Cu_(0.85)In_(0.7)Ga_(0.3)Se₂ 46.4 46.1[Cu_(0.90)In_(0.7)Ga_(0.3)(Se^(n)Bu)₃(Se^(t)Bu)_(0.90)]_(n)Cu_(0.90)In_(0.7)Ga_(0.3)Se₂ 46.5 45.9[Cu_(1.0)Ga_(1.0)(Se^(t)Bu)_(4.0)]_(n) Cu_(1.0)Ga_(1.0)Se₂ 46.7 43.0[Cu_(0.95)Ga_(1.0)(Se^(t)Bu)_(3.95)]_(n) Cu_(1.0)Ga_(1.0)Se₂ 46.9 43.1[Cu_(1.0)In_(1.0)(Se^(s)Bu)₃(Se^(t)Bu)]_(n) Cu_(1.0)In_(1.0)Se₂ 45.446.5 [Cu_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.7)Ga_(0.3)Se₂ 42.8 45.5[Cu_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)₃(Se^(t)Bu)]_(n)Cu_(1.0)In_(0.5)Ga_(0.5)Se₂ 41.3 44.8[Cu_(0.85)In_(0.7)Ga_(0.3)(Se^(s)Bu)₃(Se^(t)Bu)_(0.85)]_(n)Cu_(0.85)In_(0.7)Ga_(0.3)Se₂ 44.2 46.1[Cu_(1.0)In_(1.0)(Se(2-EtHex))₄]_(n) Cu_(1.0)In_(1.0)Se₂ 35.9 35.5[Cu_(1.0)In_(1.0)(SePh)₃(Se^(n)Hex)]_(n) Cu_(1.0)In_(1.0)Se₂ 43.4 41.5[Cu_(1.0)In_(0.9)Ga_(0.1)(S^(t)Bu)₄]_(n) Cu_(1.0)In_(0.9)Ga_(0.1)S₂ 46.244.8 [Cu_(1.0)In_(0.75)Ga_(0.25)(S^(t)Bu)₄]_(n)Cu_(1.0)In_(0.75)Ga_(0.25)S₂ 45.3 44.1 [Cu_(1.0)Ga_(1.0)(S^(t)Bu)₄]_(n)Cu_(1.0)Ga_(1.0)S₂ 41.0 40.3 [Cu_(1.0)In_(1.0)(S^(t)Bu)₄]_(n)Cu_(1.0)In_(1.0)S₂ 46.0 45.0 [Cu_(1.0)Ga_(1.0)(SEt)₃(S^(t)Bu)]_(n)Cu_(1.0)Ga_(1.0)S₂ 49.8 48.6 [Ag_(1.0)In_(1.0)(Se^(s)Bu)₄]_(n)Ag_(1.0)In_(1.0)Se₂ 49.8 49.6 [Ag_(0.6)In_(1.0)(Se^(s)Bu)_(3.6)]_(n)Ag_(0.6)In_(1.0)Se₂ 50.3 50.4 [Ag_(0.9)In_(1.0)(Se^(s)Bu)_(3.9)]_(n)Ag_(0.9)In_(1.0)Se₂ 50.3 49.8 [Ag_(1.5)In_(1.0)(Se^(s)Bu)_(4.5)]_(n)Ag_(1.5)In_(1.0)Se₂ 51.0 48.9[Ag_(1.0)In_(1.0)(Se^(s)Bu)₃(Se^(t)Bu)]_(n) Ag_(1.0)In_(1.0)Se₂ 50.849.6 [Ag_(1.0)Ga_(1.0)(Se^(s)Bu)₄]_(n) Ag_(1.0)Ga_(1.0)Se₂ 49.9 46.5[Ag_(0.8)In_(0.2)Ga_(0.8)(Se^(s)Bu)_(3.8)]_(n)Ag_(0.8)In_(0.2)Ga_(0.8)Se₂ 49.7 47.3[Ag_(1.0)In_(0.3)Ga_(0.7)(Se^(s)Bu)_(4.0)]_(n)Ag_(1.0)In_(0.3)Ga_(0.7)Se₂ 50.6 47.5[Ag_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(4.0)]_(n)Ag_(1.0)In_(0.7)Ga_(0.3)Se₂ 50.5 48.7[Ag_(1.0)In_(0.5)Ga_(0.5)(Se^(s)Bu)_(4.0)]_(n)Ag_(1.0)In_(0.5)Ga_(0.5)Se₂ 50.5 48.1[Ag_(1.0)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.0)(Se^(t)Bu)]_(n)Ag_(1.0)In_(0.7)Ga_(0.3)Se₂ 50.5 47.5 [Ag_(1.0)In_(1.0)(Se^(n)Hex)₄]_(n)Ag_(1.0)In_(1.0)Se₂ 44.5 43.3 [Cu_(0.5)Ag_(0.5)In_(1.0)(Se^(s)Bu)₄]_(n)Cu_(0.5)Ag_(0.5)In_(1.0)Se₂ 49.6 48.1[Cu_(0.7)Ag_(0.1)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.8)]_(n)Cu_(0.7)Ag_(0.1)In_(0.7)Ga_(0.3)Se₂ 51.0 47.2[Cu_(0.8)Ag_(0.2)In_(1.0)(Se^(s)Bu)₄]_(n) Cu_(0.8)Ag_(0.2)In_(1.0)Se₂46.2 47.2 [Cu_(0.2)Ag_(0.8)In_(1.0)(Se^(s)Bu)₄]_(n)Cu_(0.2)Ag_(0.8)In_(1.0)Se₂ 50.2 49.0[Cu_(0.5)Ag_(0.5)In_(0.5)Ga_(0.5)(Se^(s)Bu)₄]_(n)Cu_(0.5)Ag_(0.5)In_(0.5)Ga_(0.5)Se₂ 47.8 46.5[Cu_(0.85)Ag_(0.1)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.95)]_(n)Cu_(0.85)Ag_(0.1)In_(0.7)Ga_(0.3)Se₂ 46.8 46.1[Cu_(0.5)Ag_(0.5)In_(0.7)Ga_(0.3)(Se^(s)Bu)₄]_(n)Cu_(0.5)Ag_(0.5)In_(0.7)Ga_(0.3)Se₂ 48.5 47.2[Cu_(0.8)Ag_(0.05)In_(0.7)Ga_(0.3)(Se^(s)Bu)_(3.85)]_(n)Cu_(0.8)Ag_(0.05)In_(0.7)Ga_(0.3)Se₂ 46.0 46.3[Ag_(1.0)Al_(1.0)(Se^(s)Bu)₄]_(n) Ag_(1.0)Al_(1.0)Se₂ 41.4 43.2[Ag_(1.0)In_(0.7)Al_(0.3)(Se^(s)Bu)₄]_(n) Ag_(1.0)In_(0.7)Al_(0.3)Se₂50.3 47.9 [Cu_(0.9)Ga_(0.7)Al_(0.3)(Se^(s)Bu)_(3.9)]_(n)Cu_(0.9)Ga_(0.7)Al_(0.3)Se₂ 41.0 42.2 [Cu_(1.0)Al_(1.0)(Se^(s)Bu)₄]_(n)Cu_(1.0)Al_(1.0)Se₂ 38.2 39.2[Cu_(0.5)Ag_(0.5)In_(0.7)Al_(0.3)(Se^(s)Bu)₄]_(n)Cu_(0.5)Ag_(0.5)In_(0.7)Al_(0.3)Se₂ 46.0 46.3[Cu_(0.7)Ag_(0.25)In_(0.3)Ga_(0.4)Al_(0.3)(Se^(s)Bu)_(3.95)]_(n)Cu_(0.7)Ag_(0.25)In_(0.3)Ga_(0.4)Al_(0.3)Se₂ 41.8 44.2[Cu_(0.9)In_(0.8)Al_(0.2)(Se^(s)Bu)_(3.9)]_(n)Cu_(0.9)In_(0.8)Al_(0.2)Se₂ 46.5 45.6[Cu_(1.3)In_(1.0)(Se^(n)Bu)₃(Se^(t)Bu)_(1.3)]_(n)Cu_(1.3)In_(1.0)Se_(2.15) 47.5 46.9[Cu_(1.1)In_(1.0)(Se^(n)Bu)₃(Se^(t)Bu)_(1.1)]_(n)Cu_(1.1)In_(1.0)Se_(2.05) 46.5 46.7[Cu_(1.1)In_(0.65)Ga_(0.25)(Se^(n)Bu)₃(Se^(t)Bu)_(1.1)]_(n)Cu_(1.1)In_(0.65)Ga_(0.25)Se_(2.05) 46.1 45.5

Example 24 Controlling the Stoichiometry of the Monovalent Metal Atomsof Polymeric Precursors

FIG. 14 shows results of methods for preparing polymeric precursorembodiments (MPP) of this invention having predetermined stoichiometrywhich are useful for preparing AIS, AIGS, CAIS, and CAIGS materials ofthe same predetermined stoichiometry. The x-axis of FIG. 14 refers tothe weight percent of atoms of a particular kind, either Ag or Cu, inthe monomer compounds used to prepare the polymeric precursor. They-axis refers to the weight percent of atoms of a particular kind in thesynthesized polymeric precursor compounds. Atom concentrations weredetermined by the use of ICP. The linear correlation observed in FIG. 14for several different polymeric precursor compounds showed that thestoichiometries of the polymeric precursors were precisely controlled bythe quantities and compositions of the monomers used to make thepolymeric precursors. The linear correlation observed in FIG. 14 alsoshowed that methods of this disclosure can be used to make precursorcompounds having a range of arbitrary stoichiometries.

What is claimed is:
 1. A process for making a photovoltaic absorberlayer having a predetermined stoichiometry of a Group 11 atom on asubstrate, the process comprising depositing a polymeric precursorhaving the predetermined stoichiometry onto the substrate and convertingthe deposited precursor into a photovoltaic absorber material, whereinthe precursor has a predetermined stoichiometry according to theempirical formula M^(A1) _(x)(M^(B1) _(1-y)M^(B2)_(y))_(v)((S_(1-z)Se_(z))R)_(w), wherein M^(A1) is Cu, M^(B1) is In,M^(B2) is Ga, x is from 0.5 to 1.5, y is from 0 to 1, z is from 0 to 1,v is from 0.5 to 1.5, w is from 2 to 6, and R represents R groups, ofwhich there are w in number, which are independently selected fromalkyl, aryl, heteroaryl, alkenyl, amido, and silyl.
 2. The process ofclaim 1, wherein R is alkyl.
 3. The process of claim 1, wherein thephotovoltaic absorber material is a CIGS or CIS material.
 4. The processof claim 1, further comprising heating the substrate at a temperature offrom about 100° C. to about 650° C., thereby producing a photovoltaicabsorber layer having a thickness of from 0.01 to 100 micrometers. 5.The process of claim 1, wherein, y is from 0 to 1, z is from 0 to 1, vis from 0.9 to 1.1.
 6. The process of claim 1, wherein y is from 0 to 1,z is from 0 to 1, v is
 1. 7. The process of claim 1, wherein y is from 0to 1, z is from 0 to 1, v is
 1. 8. The process of claim 1, wherein theprecursor has a predetermined stoichiometry of a CIGS or CISphotovoltaic absorber material.
 9. The process of claim 1, wherein aprecursor is deposited in an ink composition.
 10. The process of claim1, wherein the depositing is done by spraying, spray coating, spraydeposition, spray pyrolysis, printing, screen printing, inkjet printing,aerosol jet printing, ink printing, jet printing, stamp printing,transfer printing, pad printing, flexographic printing, gravureprinting, contact printing, reverse printing, thermal printing,lithography, electrophotographic printing, electrodepositing,electroplating, electroless plating, bath deposition, coating, wetcoating, dip coating spin coating, knife coating, roller coating, rodcoating, slot die coating, meyerbar coating, lip direct coating,capillary coating, liquid deposition, solution deposition,layer-by-layer deposition, spin casting, solution casting, orcombinations of any of the forgoing.
 11. The process of claim 1, whereinthe substrate is selected from the group of a semiconductor, a dopedsemiconductor, silicon, gallium arsenide, insulators, glass, molybdenumglass, silicon dioxide, titanium dioxide, zinc oxide, silicon nitride, ametal, a metal foil, molybdenum, aluminum, beryllium, cadmium, cerium,chromium, cobalt, copper, gallium, gold, lead, manganese, molybdenum,nickel, palladium, platinum, rhenium, rhodium, silver, stainless steel,steel, iron, strontium, tin, titanium, tungsten, zinc, zirconium, ametal alloy, a metal silicide, a metal carbide, a polymer, a plastic, aconductive polymer, a copolymer, a polymer blend, a polyethyleneterephthalate, a polycarbonate, a polyester, a polyester film, a mylar,a polyvinyl fluoride, polyvinylidene fluoride, a polyethylene, apolyetherimide, a polyethersulfone, a polyetherketone, a polyimide, apolyvinylchloride, an acrylonitrile butadiene styrene polymer, asilicone, an epoxy, paper, coated paper, and combinations of any of theforgoing.
 12. A photovoltaic absorber material made by the process ofclaim
 1. 13. A photovoltaic device made by the process of claim
 1. 14. Aprocess for providing electrical power comprising using a photovoltaicdevice according to claim 13 to convert light into electrical energy.15. The process of claim 4, wherein the substrate is heated at atemperature of from about 100° C. to about 550° C.
 16. The process ofclaim 4, wherein the thickness is from 0.05 to about 5 micrometers. 17.The process of claim 4, wherein the polymeric precursor is deficient inCu.
 18. The process of claim 4, wherein the polymeric precursor isenriched in Cu.